The Effectiveness And Safety Of Fire Hoods

Transcription

The Effectiveness And Safety
Of Fire Hoods
JBG Johnstone, RA Graveling, DO Butler
MP Butler, HA Cowie, MA Hanson
October 1995
IOM Report TM / 96 / 04
Report No. TM/96/04
INSTITUTE OF OCCUPATIONAL MEDICINE
THE EFFECTIVENESS AND SAFETY
OF FIRE HOODS
JBG Johnstone, RA Graveling, DO Butler
MP Butler, HA Cowie, MA Hanson
Institute of Occupational Medicine
8 Roxburgh Place
Edinburgh EH8 9SU
Tel 0131 667 5131
Fax 0131 667 0136
This report is one of a series of Technical Memoranda (TM) distributed by the Institute of
Occupational Medicine. Current and earlier lists of these reports and of other Institute publications,
are available from the Technical Information Officer/Librarian.
CONTENTS
Page
SUMMARY
1.
2.
INTRODUCTION
1
1.1
Background to the Study
1
1.2
Objective
2
1.3
Relevant Literature
2
1.4
Project Plan
3
METHODS
2.1
5
Survey of Fire Hoods within Brigades
and External Institutions
2.1.1
Introduction
2.1.2
Brigade questionnaire
2.1.3
Operational questionnaire
2.1.4
Distribution of questionnaires
2.1.5
External companies/brigades
5
5
5
5
5
5
2.2
Subjective Responses to Fitting Trials
2.2.1
Introduction
2.2.2
Subjective testing protocol
6
6
6
2.3
Subjective Responses During Training Exercises
2.3.1
Introduction
2.3.2
Development of questionnaire
2.3.3
2.3.4
Training exercises
7
7
7
7
7
2.4
Observational
2.4.1
2.4.2
2.4.3
2.4.4
8
8
8
9
9
2.5
Physical Tests
2.5.1
Introduction
2.5.2
Radiant heat transfer
2.5.3
Closeness of
2.5.4
Oven tests/heat build-up tests
Trials
Introduction
Selection of fire house and firefighters
Observational trials
Method
fit
11
11
11
12
12
3.
2.6
Audiometric/Sound Location Tests
2.6.1
Introduction
2.6.2
Selection of subjects
2.6.3
Sound attenuation test equipment and procedure
2.6.4
Sound location test equipment and procedure
13
13
13
13
13
2.7
Physiological Load Imposed by the Hoods
2.7.1
<
Introduction
2.7.2
Method
14
14
14
2.8
Statistical Methods
16
RESULTS
17
3.1
Survey of Fire Hoods within Brigades
3.1.1
3.1.2
Operational firefighter questionnaire
3.1.3
Survey of external companies/international brigades
3.1.4
Injury reports
17
17
17
18
18
3.2
Hoods Used for Trials
19
3.3
19
3.4
Subjective Responses to Wearing Fire Hoods During Training Exercises
3.4.1
Introduction
3.4.2
Attitudes to hoods
3.4.3
Findings for individual hoods
3.4.4
Summary of comments
21
21
21
21
26
3.5
Observational
3.5.1
3.5.2
3.5.3
3.5.4
3.5.5
26
26
27
27
28
28
3.6
Physical Tests
3.6.1
Radiant heat transfer of fire hoods
3.6.2
Closeness of
3.6.3
Oven test/heat build-up tests
Trials
Data and statistical analysis
Time to complete exercise
Subjective awareness of temperature
Behavioural responses
Subjective responses
fit
s
29
29
30
30
3.7
3.7.1
Audiometric tests
3.7.2
Sound location tests
30
30
30
3.8
Physiological Loads Imposed by the Hoods
3.8.1
Physiological data
3.8.2
Subjective data
31
31
32
4.
DISCUSSION
35
4.1
Survey Responses
35
4.2
Subjective Responses to Fitting and Wearing Fire Hoods
35
4.3
Behavioural Trials
38
4.4
Physical Tests
39
4.5
40
4.6
Physiological Load
40
4.7
General Discussion
41
5.
CONCLUSIONS
43
6.
RECOMMENDATIONS
45
ACKNOWLEDGEMENTS
47
REFERENCES
49
TABLES
FIGURES
APPENDICES
Report No. TM/96/04
INSTITUTE OF OCCUPATIONAL MEDICINE
THE EFFECTIVENESS AND SAFETY OF FIRE HOODS
by
JBG Johnstone, RA Graveling, DO Butler, MP Butler,
HA Cowie, MA Hanson
SUMMARY
To avoid confusion, the terminological convention which emerged within the fire service during
the life of the project is adopted in this report. The term 'anti-flash hood' will therefore be
reserved for hoods meeting the E9 specification. Balaclava-style hoods will be referred to as
Tire hoods'.
In recent years, there has been a growing interest within the fire service in the use of balaclava-style
fire hoods as an alternative to, or replacement for, the E9 specification anti-flash hood. This report
describes the results of a project, commissioned by the Home Office, to investigate aspects of the use
of fire hoods by operational firefighters. It examined elements of the effectiveness of the fire hood
in terms both of heat exclusion (particularly radiant heat protection) and heat retention. It also
addressed safety issues, notably concerns expressed by an appreciable number of firefighters that they
would be more isolated from their working environment whilst wearing such hoods and, possibly as
a result, that wearing a hood would engender different attitudes to firefighting risks, resulting in a
detrimental effect on behaviour.
The project firstly demonstrated an undoubted need for some such protection as shown by the high
proportion of reported burn injuries involving injury to those areas of the head and neck which were
usually exposed, but would have been covered by a fire hood if worn. It also showed that, although
there were some specific design shortcomings with some fire hoods, the head coverage and fit
provided by most hoods was adequate as was the level of radiant heat insulation. Despite this
insulative effect, the impact of wearing a fire hood on heat retention and body temperature was not
significant. Although the head is potentially an efficient avenue for heat loss, the existing coverage
by helmet and BA face mask is such that the additional coverage by a fire hood does not have any
real effect.
Another safety concern addressed was that of heat awareness and the related issue of heat flow around
the head and up into the helmet. Trials showed that firefighters are not particularly good at accurately
assessing the environmental temperature and that wearing a fire hood did not cause any significant
deterioration in their abilities in this respect. Laboratory tests showed how a fire hood could insulate
the scalp from heat flowing into the helmet head space. There were however indications that the
fabric skirts fitted to the rear of many modern styles of helmet could channel heat into this space,
potentially causing greater thermal discomfort.
Because fire hoods cover the ears of the firefighter, it has been suggested that this might have a
potentially hazardous impact on hearing ability. The project examined two aspects of this. Firstly,
it quantified the noise attenuation characteristics of a variety of hoods, showing these to be negligible.
Secondly, it looked at the impact of the fire hoods on sound location, systematically evaluating the
ability of a wearer to identify the direction from which a DSU noise was coming from against a
background of fireground noise. Again, the results showed this concern to be unfounded. However,
a novel, wrap-round, design of helmet, which was investigated as part of this element of the study,
did have some detrimental impact both on noise attenuation (there was some evidence of a resonance
effect within the head shell at certain frequencies) and on sound location.
Finally, observational trials of firefighters wearing fire hoods during a live-fire, search and rescue
exercise, did not show any systematic impact of fire hoods on safe working practices either by staying
in hot areas for longer or by neglecting standard safety procedures. What became apparent during
these exercises however was a considerable variety of approaches between different brigades. This
suggests possible benefits could be obtained from standardising between brigades on best practice in
training.
1
1. INTRODUCTION
1.1
Background to the Study
In 1977, a specification for a curtain-type loose fitting anti-flash hood was issued (E9). This
device was designed to fit quickly and easily over a firefighter's helmet and breathing
apparatus (BA), giving the general appearance of a beekeepers hood. It was intended to be
worn for limited durations in circumstances where there was a possibility of a flashover
occurring and was not for use during general firefighting. Subsequently, consideration was
given to the relative benefits of balaclava style hoods, either close or loose fitting. In 1982,
the British Clothing Centre pointed out that the E9 style would give better protection because
of the contained air but that a balaclava style might be better for general use, recommending
a loose-fitting style apparently as a compromise because of its ability to trap some air.
In 1984, the Joint Committee on Appliances, Equipment and Uniform (JCAEU) decided that
the E9 was best for foreseeable flashover conditions, further stating that:
'the Fireman's neckerchief and the anti-flash hood offered adequate
protection and the introduction of the balaclava type garment could restrict
a fireman's sense of awareness and security and tend to be used only to keep
warm.'
Despite this conclusion, brigades apparently remained unconvinced (a) that the E9 was the
best option and (b) that there was not a role for balaclava style hoods. In 1985, a short report
was published of work involving Tyne and Wear Metropolitan Fire Brigade (Stevenson,
1985). This commented on a number of adverse skin effects of heat exposure and
recommended that firefighting instructors (the subjects of the study) should wear protective
'flash-hoods' on a regular basis although the type of hood tested was not stated. A report was
produced by London Scientific Services (LSS) in 1989 which indicated that an example of one
such hood appeared to provide good protection to both flame and heat and would seem to be
appropriate for general fire use.
In 1991, as part of a project on the physiological effects of wearing breathing apparatus
carried out by the Institute of Occupational Medicine on behalf of the Home Office (Love et
al. 1994) a questionnaire survey was carried out involving all brigades in the UK. As an
adjunct to the main purpose of the questionnaire, questions were also asked regarding the use
of protective hoods.
The analysis of the questionnaires revealed that brigades were using a variety of loose and
close fitting hoods/balaclavas:
(i)
eleven brigades had the specification E9 anti-flash hood;
(ii)
eight brigades had close fitting anti-flash balaclavas;
(iii)
one brigade had general purpose balaclavas;
(iv)
one brigade had snoods ie. a balaclava that rolls down, when
not in use, to provide neck protection; and
(v)
two brigades had both E9 and close fitting anti-flash hoods
available.
Many of the brigades not providing their firefighters with any form of anti-flash protection
reported that they were awaiting national guidance.
1.2
Objective
Against this background, the Home Office decided to commission this study into the
effectiveness and safety of fire hoods with the following stated objective:
To carry out a study, under controlled conditions, in order to investigate whether there are
inherent dangers to firefighters when wearing either close fitting anti-flash balaclavas or
general purpose balaclavas owing to the fact that:
(i)
there is a possibility that, because of the absence of an air space
between the balaclava helmet and wearer due to the close fit, the risk
of firefighters receiving burns in environments when direct exposure
to the air temperature would present no such risk may be increased;
(ii)
the wearing of balaclava hoods for long periods could exacerbate the
conditions leading to heat stress;
(iii)
the use of balaclavas could result in firefighters becoming less
sensitive to increases in temperature thereby inducing a false sense
of security leading them to remain in potentially life threatening
situations; and
(iv)
the seal of the breathing apparatus face mask may be compromised.
Two specific work packages were identified by the Home Office to achieve this objective:
1. To ascertain the type of protective hoods used by firefighters and the
circumstances in which they are used.
2. To investigate the inherent dangers to firefighters when wearing balaclava
anti-flash hoods (fire hoods).
1.3
Relevant Literature
Apart from the paper by Stevenson (1985) cited above, no references to work on anti-flash
hoods, flash hoods or fire hoods could be found in a search of British, European and
American literature databases.
Articles in 'trade' journals generally summarised
manufacturer's advertising information and did not assess the actual performance of the antiflash hoods.
1.4
Project Plan
The aim of work package 1 was achieved by carrying out a survey throughout the UK at both
brigade and operational firefighter level. This study aimed to collate information on how
widely fire hoods were distributed in the brigades and whether those that did not use them
were in the process of evaluating any. The questionnaire distributed to the operational
firefighters was used to determine attitudes to fire hoods and to identify any problems which
had arisen since the fire hoods were introduced into the brigades.
The aim of work package 2 was achieved by simulating a number of exercises and measuring
firefighters' physiological and subjective performance when wearing fire hoods. This part
of the study also involved assessing the restriction of movement resulting from the wearing
of fire hoods and the physical performance of the fire hoods; and collating firefighters
perceptions of them.
During the life of the project, several helmet manufacturers started to supply helmets fitted
with a short flap of material known as skirts (also known as neck curtains or earflaps).
Enquiries amongst brigades revealed that some were tending to regard them as an alternative
to a fire hood, whereas others had already issued fire hoods and were concerned about the
implications of wearing both together. Furthermore, others were concerned about an alleged
tendency of skirts to funnel heat up into the helmet and had, therefore, ceased using them.
Because of these concerns, the project remit was extended to include helmet skirts in selected
tests in work package 2 and also, as a logical extension of this, to incorporate the close-fitting
helmet system manufactured by Gallet into relevant tests.
5
2. METHODS
2.1
Survey of Fire hoods within Brigades and External Institutions
2.1.1
Introduction
Information needed to be gathered on the different hoods used within the brigades as well as
on those available but not currently in use. The format used in previous IOM studies eg.
Love et al. (1994) was followed by using two questionnaires, one to collect brigade
information, the other for individual firefighters. The initial draft questionnaires were pilot
tested in Central Region Fire Brigade, which provided an opportunity to clarify the questions
raised and to add additional topics. Both questionnaires were integrated with those being used
concurrently for another project on the degree of protection afforded by firefighters' clothing.
2.1.2
As can be seen from the sample questionnaire in Appendix A, the brigade questionnaire was
designed to obtain factual information; section J related specifically to fire hoods. The
section requested details about the fire hoods currently used by the brigade including when
they were introduced and in which operational and training situations they would be worn.
There was also a section covering any evaluations of fire hoods being carried out for those
brigades not currently using fire hoods.
2.1.3
Operational questionnaire
As can be seen in Appendix B, section F of the operational questionnaire was devoted to fire
hoods. This questionnaire was designed to ascertain the firefighters' opinions on the fire
hoods they wore and to assess whether they believed they were being over-protected by
wearing them. It also asked in what training and operational situations a fire hood would be
worn.
2.1.4
All sixty-seven brigades in the UK were sent copies of both questionnaires with a request that
the brigade questionnaire be completed by an appropriate person at brigade headquarters.
Approximately one thousand operational questionnaires were distributed to a random sample
of one station in every six, each receiving three questionnaires; two to be completed by
firefighters and one by a leading firefighter. The liaison officer in each brigade was asked
to pass the individually coded questionnaires to a preselected set of stations. Both whole-time
and retained stations were included in the survey.
In total, 337 stations received a total of 1011 questionnaires. Replacement questionnaires
were sent out after a month to those brigades who had not returned the originals. A total of
1045 questionnaires were distributed in the UK including the replacements.
2.1.5
External companies/brigades
Other potential users of fire hoods were also contacted to find out if any other types of hood
were in use and how widespread the use was. Several overseas brigades were contacted.
Within Britain, companies and airports with private fire crews were also contacted.
6
2.2
2.2.1
Introduction
The subjective assessments of the fire hoods were carried out as part of a larger study into
the protection afforded by firefighters' clothing. Over a period of twelve weeks firefighters
from brigades throughout the country assessed a range of different hoods for restriction of
movement. The assessments evaluated the wearability of the hood in terms of fit and effect
on freedom of movement together with the compatibility of the hood with other items of
protective equipment such as the helmet and BA face mask.
2.2.2
Subjective testing protocol
Seventy firefighters from 17 brigades took part in the fire hood fitting trials which comprised
two conditions. The first investigating the use of fire hoods when BA was not worn, and the
second looking at the use of fire hoods when BA was worn. The subjects were shown the
correct way of putting on a fire hood before the first assessment was carried out.
The procedure for the first fitting trial condition was as follows: the subject donned one of
the fire hoods being evaluated and then put on his helmet. Having done this he was asked
to comment on the degree of difficulty that these actions entailed by completing a
questionnaire (see Appendix C for the questionnaire used in the assessment). He then
undertook a series of movements selected to reproduce the full range of movements that a
firefighter was likely to make during the execution of his duties. Such movements included
turning the head from side to side and tilting the head forwards and backwards. The subject
spent typically one minute carrying out each movement per condition per trial. After each
movement, he was asked a series of short questions about whether the fire hood or helmet
had slipped out of position as a result of the movement; whether any yoke on the fire hood
had restricted the movement in any way; whether any part of the subject's equipment had
caused any discomfort during the movement. If the subject answered 'YES', to any of these
questions, he was asked to elaborate on his answer and explain where restrictions occurred,
or what caused the discomfort. Once the subject had completed the sequence of movements
and had answered all the associated questions he carried out the second fitting trial condition
involving the use of BA. In this condition the subject removed his helmet and pulled the
hood back off his head so that it lay around his neck. Then he donned his BA and pulled the
hood back up over his head and the BA mask-retaining harness, so that the facial aperture in
the hood fitted snugly around the facepiece of the mask. Having successfully completed this,
the fitting trial proceeded in a similar way to the first condition as described above.
However, additional questions were asked after each movement regarding the interaction of
the fire hood with the BA mask and an extra movement, checking the cylinder pressure
gauge, was added to those used during the first wearer trial condition.
This protocol was only used for fitting trials carried out on the balaclava type fire hoods.
The procedure for fitting trials involving the E9 'beekeeper' anti-flash hood was necessarily
different as this hood does not fit over the head directly but fits over the helmet, which in
turn fits over the head. Consequently the anti-flash hood should not come into contact with
the wearer's face at all. The assessments of the E9 anti-flash fire hood were carried out only
for the 'with BA' condition as it is not worn without BA.
7
2.3
Subjective Responses During Training Exercises
2.3.1
Introduction
As it was believed that many of the firefighters who discussed fire hoods during the fitting
trials had preconceived ideas about their efficacy without ever having worn them, another
assessment of the hoods was devised in order to gather information on firefighters'
perceptions and evaluations of fire hoods after having worn one during a training exercise.
Training exercises were selected for these tests to enable the firefighters to be exposed to high
temperature conditions in which they would be able to feel the effect of wearing a fire hood
and judge whether in such situations it was detrimental to their ability to assess the
environment or provided them with an extra level of protection. The benefit of using a
training situation was that the environment was well controlled and the same scenario could
be carried out by each team of firefighters. These trials were used to evaluate all of the fire
hoods available on the market at the time of the study.
2.3.2
Development of questionnaire
Based on the comments gathered from the fitting trials a questionnaire (Appendix D) was
drawn up asking firefighters about their knowledge and experience of wearing fire hoods;
the interactions caused by wearing a fire hood; and aspects of the hoods in terms of comfort
and design.
2.3.3
The questionnaires were sent out to liaison officers at the training centres of six brigades,
three of which were already using fire hoods. Each of the brigades was supplied with nine
fire hoods (three hoods of three different types). Each fire hood was to be assessed by two
brigades. The questionnaires and hoods were sent to the officer with comprehensive
instructions for the liaison officer which included instructions on how to put a fire hood on
correctly and a test protocol. A copy of the test protocol can be found in Appendix D.
These initial trials did not generate sufficient data to allow adequate evaluation and a second
phase was carried out at the Scottish International Fire Training Centre where all of the hoods
were assessed by Lothian and Borders fire brigade personnel. Each was evaluated by twelve
wearers from various stations throughout the brigade.
2.3.4
Training exercises
The firefighters were asked to wear a fire hood when attending their BA refresher course.
They were first instructed as to how to put the fire hoods on correctly. The firefighters then
wore the fire hoods for one or two hot exercises in temperatures typically of 110-120°
involving live fires and then completed the questionnaire. The actual exercise scenarios were
devised and conducted by the staff of the training centre.
2.4
Observational Trials
2.4.1
Introduction
The stimulus for this element of the study centred on the widely held view that "the use of
balaclavas could result in firefighters becoming less sensitive to increases in temperature
thereby inducing a false sense of security, leading them to remain in potentially life
threatening situations" (Home Office Research Proposal).
Personal protective clothing essential for safe fire fighting duties requires a level of insulation
which inherently leads to the senses of the majority of the wearers becoming masked. Many
firefighters have stated that they depend heavily on their ears to alert them to both the
direction of the seat of the fire and the temperature. With the introduction of the fire hood
many saw this last sense as also being restricted, and thus dangerous in terms of their loss
of thermal sensitivity and overall awareness.
In the light of this concern a study was constructed to address the theory that those
firefighters wearing fire hoods may be liable to remain in dangerous situations without
realising the possible consequences to their safety.
A working group was set up to guide the research. Representatives from the Fire Research
Development Group (FRDG), UK brigades and the IOM met to discuss both the content and
the logistics of such a study.
It was decided that the main criterion for judging the efficacy of a fire hood would be the
time taken to perform a given task, on the basis that the ability to 'just get on with the job'
would be a likely benefit. However, it was recognised that, in engendering this attitude,
wearing a fire hood might result in a firefighter taking more or undue risks. For example,
by feeling more protected, the firefighter might not adhere to normal protocols for entering
closed rooms and, in the interests of more rapid progress, safety search patterns, eg. for
damaged or obstructed flooring, might be neglected.
A scenario was therefore required which would have a finite duration but could incorporate
various 'test' points at which behaviour could be evaluated against accepted standard
procedures. It would clearly be essential if this is to be successful, to ensure that the
procedure regarded as standard was that taught within participating brigades.
One scenario which appeared to meet most, if not all, the requirements identified consisted
of the rescue of a casualty from a house fire.
2.4.2
Selection of fire house and firefighters
Letters detailing the aims and the requirements of the study were sent to all the major UK fire
training centres. The recently built fire house for the Royal Berkshire Fire & Rescue Service
was chosen as being the most suitable for the research.
The fire house at Berkshire incorporates two important design features which make objective
data collection more practicable. The complex is run from a central control room where a
console continually displays the temperatures at both mid and ceiling level on all floors. In
addition, each floor is covered by an integrated monitoring system combining microphones
and radar movement detectors, the signals from which are relayed to the control room
console. This sophisticated monitoring equipment allows accurate matching of environmental
temperatures with the location of the firefighters in the building.
Firefighters from surrounding brigades were invited to take part in the research. In total, 55
firefighters from the following five brigades took part. Ten from Oxfordshire (mean age 34.6;
mean number of years experience 9.8), 16 from Berkshire (27.8; 4.3), 3 from
Buckinghamshire (37.6; 2.5), 5 from South Glamorgan (32.4; 10) and 21 from Hampshire
(37.8; 15.5).
2.4.3
Observational trials
Both the ground and first floor of the fire house were utilised. The room layouts are shown
in figures 2.1 and 2.2 (ground and 1st floor respectively). The firefighter entered the
building, (see entrance point, figure 2.1) and adopted a right-hand search, thus keeping away
from the burn room located in the centre of the floor. This right-hand search led to the start
of the stairs, the first floor landing, then the right hand wall reaching the lounge, (figure 2).
After a thorough search of this room the firefighter moved from this room to the bedroom.
After locating the casualty the firefighter returned by the reverse route.
To address the question of increased risk to firefighters in terms of length of time spent in
a life threatening situation, 'time zones' were set-up throughout the two floors. The start and
stop times of the zones were relayed to the control room operator from the observer via a two
way radio system. When the firefighter entered the building the observer instructed the
control room staff to start recording time spent in zone 1. This time recording was stopped
when the control room operator was informed that the firefighter had located the base of the
stair case. The recording in zone 2 was then started and continued until the 1st floor entry
door. Recording in zone 3 was then started and lasted until the firefighter reached the
bedroom door. Zone 4 was recorded from entering the bedroom door to exiting the bedroom
door, and zone 5 was then from the bedroom door until they exited the building. Time in
zone 2 was seen as particularly important as this zone covered the locality of the burn room
where the highest temperatures were to be found. A propane powered industrial space heater
was used in zone 4 in an attempt to create an additional hot spot. However, this was always
turned off before the firefighter entered the building.
2.4.4
Method
Firefighters were required to complete a medical disclaimer and to listen to the safety
briefing.
To maximise the number of participants, and therefore the reliability of the results, subjects
were instructed that they were to complete the exercise individually, but to imagine that they
were part of a team and thus to verbalise and act accordingly. It was stated that an IOM staff
member would be beside the firefighter at all times and that a safety officer would be in the
area.
During each day there was an average of three exercises or burns, two in the morning and
one in the afternoon. Each exercise lasted for approximately one hour, and two firefighters
went through each exercise.
The first pair got changed into full fire kit for each exercise. All helmets, gloves, fire hoods
and skirts were provided. Firefighters were issued with an F500 helmet, being the model
10
currently in use by more firefighters than any other. As appropriate, this was provided fitted
with a Nomex skirt from the same suppliers. When a fire hood was issued, that
manufactured by Mattinsons was provided, again selected on the basis of being the
commonest issued. During the exercises all firefighters were also issued with Firecraft
gauntlet style gloves. These were standard issue at the Training Centre. Each firefighter was
given the equipment according to which condition he or she was testing, taken out to the
training ground, and given the following instructions.
You are part of an imaginary crew who have been called to an incident at a two storey
premises which consists of a flat above a small corner shop. There has been an explosion
affecting mainly the ground floor but it is clear that smoke, fire and heat may well have now
spread to the first floor. You have been informed that there is a child missing who lives with
the family in the first floor flat, and she has been seen at a bedroom window. Your task is
to enter the building on the ground floor and proceed to search for the missing child. You
may assume the presence of an imaginary BA team partner.
Safety Note: You will be observed at all times by qualified safety personnel.
The first firefighter was then prepared for entering the building. An obscuration mask (used
to simulate a smoke-filled atmosphere) was fitted to the BA face mask before he donned it.
Fitting of the hood/skirt was checked by the IOM staff before any firefighter entered the
building. The second firefighter in the team acted as BA entry control officer for the
incident.
When ready, the firefighter was led to the entry door and told to start, (under instructions to
adopt a right-hand search pattern). On entering, the control room staff were informed and
timing commenced for the exercise in the first zone. The firefighter was watched throughout
the exercise and judged on the following factors:
(1)
(2)
(3)
(4)
Did
Did
Did
Did
they
they
they
they
request Gauge checks?
follow correct door procedures?
follow the correct stair procedures?
undertake a thorough search?
After the firefighter came out of the building, the second one went in and completed the same
procedure.
Both firefighters then completed a questionnaire, the construction of which was dependent on
the condition undertaken. Those undertaking the 'control' condition were required to draw
a plan, as they recalled it, of the ground and first floor. They were also asked to estimate
the temperature that they had been exposed to in zones 1, 2 and 4. Those wearing the hood
and/or skirt completed an additional self-administered questionnaire.
The timings and actual temperatures were obtained from the control room staff and affixed
to the appropriate subject's file which also contained the judgements of the safety personnel
and observer on the four factors listed above. (Appendix E gives examples of the various
questionnaires and recording sheets).
11
2.5
Physical Tests
2.5.1
Introduction
Fire hoods can have conflicting effects on heat transfer between the environment and the
wearer's head. Firstly the fire hood may prevent direct burns to the skin of the face and neck
by acting as a barrier between the heat source and the skin thus preventing the rapid inward
flow of heat. In a previous study carried out by the IOM (Graveling et al. 1996) a survey
of injuries to firefighters identified that burns to the neck and lower face were the most
commonly reported burn injury. Secondly, the fire hood may prevent heat loss through the
head and therefore contribute to the heat retained in the body, possibly leading to a rise in
core temperature.
As part of the overall evaluation of fire hoods, physical tests of their heat transfer properties
were undertaken. In addition, during the life of the project, the possible influence of helmet
skirts and close-fitting helmets, such as that manufactured by Gallet, on heat build-up around
the head was addressed by means of further tests.
2.5.2
Radiant heat transfer
Fire hoods
Method
The fabric was tested in a manner comparable to that described in British Standard 3791 part
D: Radiant Heat Transfer Tests. In order to ensure that the sample was tested in a similarly
stretched condition to that worn by a firefighter, a standard amount of stretching of the fabric
sample was simulated. This was achieved by placing the fire hood on a standard sized model
head (QA070). A square (100mm by 100mm) was marked on the fabric while it was
stretched in this way. The fire hood was removed from the model head, and placed into the
test frame according to BS3791 Part D. When positioning the sample into the frame the
material was stretched so that the marked square exactly covered the test frame. In
compliance with BS3791 Part D a standard copper disk of 15mm diameter and a thermistor
were placed behind the test material: the stretched fabric was touching this copper disc
during the test.
The temperature of the thermistor was recorded at the start of the experiment. A standard
radiant heat source (lOkwm'2) was positioned 10.5mm from the test material. The radiant
heat source was turned on and the time taken for the temperature of the thermistor to rise by
25°C was recorded. As the fabric was heated any signs of scorching of the material,
production of fumes etc. were noted. This test was repeated five times for each fire hood.
Each test was conducted over a previously untested part of the fabric.
The thickness of fabric when tested was consistent with the thickness of the fabric of the fire
hood when worn. For example some fire hoods were constructed with a double thickness of
material over the head and a single thickness for the cowl. In this case the fabric was tested
with two layers of material. Testing was not carried out over ear holes or seamed pieces of
fabric.
E9 anti-flash hood with standard fire hood
12
Method
The above test procedure was modified slightly to allow the E9 anti-flash hood to be tested
in a comparable fashion. The E9 hood was attached to a standard Firebird helmet, and the
helmet placed on a standard sized model head (QA070). The distance of the E9 fabric from
the neck of the model was measured at its closest point. This was found to be approximately
10cm. The test apparatus was then set up to simulate this wearing condition. The E9 fabric
was placed 10.5mm from the heat source. The temperature sensing probe was positioned
10cm behind this. The heat source was switched on, and the increase in temperature after
45 seconds and 120 seconds was recorded. In a second test, the probe was covered with the
Cairns and Brother Nomex fire hood that had been stretched in a standard way as described
above. The E9 anti-flash hood was used with a fire hood in this way as, if fire hoods become
used as a matter of routine then the E9 hood may be worn additionally rather than as an
alternative.
As the fabric was heated any signs of scorching of either material and/or the production of
fumes were noted. Both tests were repeated five times, and were conducted over a previously
untested part of the fabric.
2.5.3
Closeness of fit
Each of the fire hoods was tested in the following way. A 100mm horizontal line was
marked on the fire hood at a distance of 100mm from the middle of the top of the fire hood.
The fire hood was placed on a standard model head QA070, and the length of the marked line
was measured. This indicated the extent of stretching of the fabric. Any looseness in the fit
of the fire hood was noted, and the amount of spare material round a fixed point on the neck
of the standard model was measured.
2.5.4
Oven tests/heat build-up tests
Heat transfer through different fire hoods having been addressed previously (see section
2.5.2), the main focus of these tests was on the interactions between fire hood, helmets and
helmet skirts. Consequently, only one type of fire hood was employed as standard throughout
this series of tests.
Five different head protection ensembles were selected to evaluate heat build up against a
control (without any head protection). The five ensembles were the Gallet helmet, a
Cromwell helmet, a Cromwell helmet with a fire hood, a Cromwell helmet with a skirt and
a Cromwell helmet with both a fire hood and a helmet skirt. Each of these combinations
were assessed in two oven tests. The first test involved the ensembles being placed in an
oven at 250°C for 3V4 minutes. This test, based on the American NFPA helmet test (NFPA,
1987) was followed by a longer duration test of 10 minutes at the lower temperature of
200°C. At the end of the tests the surface temperature of the head was measured on the top
of the model head (inside the helmet). Each of the tests was carried out in duplicate.
13
2.6
2.6.1
Introduction
Apart from their impact on the inward or outward flow of heat energy, firefighters have often
expressed concern that the fire hood covering their ears will, in some way, affect their ability
to hear properly. It has been suggested, firstly, that a fire hood could attenuate the sound
pressure level at the subject's ear by placing a barrier between the sound source and the ear
and secondly, that a hood could affect a firefighter's ability to locate the direction of discrete
sound sources by affecting the sound location properties of the pinna (outer ear).
If valid, both of these effects could have serious implications for the ease with which
firefighters expect to be able to carry out their job. Attenuating the sound level would make
it more difficult to understand speech and to detect sound cues in the environment. Affecting
the sound location ability of the firefighter would make it more difficult for them to determine
the direction from which a warning signal, such as a DSU (Distress Signal Unit), is coming,
and may hamper efforts to locate fire in a smoke filled room.
2.6.2
Selection of subjects
Eight subjects were randomly selected from volunteers within the Lothian and Borders Fire
Brigade; all subjects were male. The mean age was 35 years (range = 27-47 years); mean
number of years experience was 13 years (range = 1-22 years). All the subjects underwent
an audiometric assessment prior to taking part in the experiment and none was found to have
any significant hearing loss.
2.6.3
Sound attenuation test equipment and procedure
The tests were conducted in a sound dampened room with loudspeakers arranged to ensure
an even distribution of sound. Pre-recorded sound (white noise) was amplified and presented
in the room at an approximate intensity of 75dB(A). Two microphones were used, one to
receive sound outside and the other inside the fire hood in the manner described below and
the outputs fed through a differential amplifier to an IVIE (IVIE Electronics Inc.) sound level
meter. The use of a differential amplifier provided a single output representing the difference
in sound level between the two microphones.
Before the formal testing began, control readings were obtained from the two microphones
to allow for slight differences in sensitivity between them. Following this, the subject sat on
a chair in the sound dampened room whilst one of the pair of microphones was located,
pointing outwards, in his ear. Then the subject put on his fire hood and the second
microphone was attached to it, pointing outwards from the subject's head on the same vertical
axis as the first microphone but positioned 25mm lower. The white noise was switched on
and the differential readings recorded for each of the third-octave bands from 63Hz to
8,OOOHz. The difference between the control readings and the test readings was calculated
for each hood. The noise attenuation test, as described above, was carried out twice during
each visit.
2.6.4
Sound location test equipment and procedure
The loudspeakers used in the attenuation tests was supplemented by eight small speakers
which produced the signal to be located against the background noise presented through the
14
main speakers. These were arranged at 45° intervals in a circle round the subject position.
For the sound location tests a pre-recorded DSU signal was channelled to the selected
speaker. The sound level of the background noise (pre-recorded fireground noise) was set
to 75dB(A) whilst that of the DSU sound was set to 95dB(A) using a sound level meter.
Each subject was told that he would be exposed to a fireground noise, over which a DSU
sound would be periodically presented, and that his task was to identify which of the eight
small loudspeakers the DSU sound was coming from and to record its number on the record
sheet (see Appendix F). The subjects were informed that they were free to move their heads
if this would assist in carrying out the task.
On their first visit, each subject undertook the sound location tests twice; once without a fire
hood, and once whilst wearing a fire hood. Thereafter each subject only carried out the test
once whilst wearing a fire hood.
2.7
Physiological Load Imposed by the Hoods
2.7.1
Introduction
Firefighters who have worn fire hoods have expressed concern that they retain metabolic heat,
resulting in the reduction of any potential heat loss from the body via the head. A study was
devised to assess the impact of fire hoods on the overall ability of firefighters to lose heat.
In addition to testing the physiological effect of wearing a fire hood, it was decided also to
investigate the physiological effect of wearing helmet skirts and their interaction with fire
hoods. These skirts can be attached to conventional helmets. In addition, a further style of
helmet, the Gallet, which is more enclosing than a conventional helmet and therefore
potentially more insulating, is also available with a helmet skirt.
Tests were conducted in order to determine the physiological impact on the firefighter of
wearing a fire hood with one of two lengths of helmet skirt and standard fire kit. In addition,
tests were conducted to determine the physiological effect of wearing a Gallet helmet both
with and without a helmet skirt.
2.7.2
Method
The two types of fire hood selected for use were those performing best in the radiant heat
tests (ie. most insulating). As the E9 anti-flash hood provides radiant rather than conductive
insulation it was not included in these trials. A single conventional helmet (Firebird) with
either a long or a short skirt attached, or the Gallet helmet, was worn. The control condition
for comparison was the conventional helmet with no skirt fitted and with the fire hood worn
around the neck in the style of a neckerchief as is common practice. The same eight subjects
participated in the trials as described in section 2.6.2. Their mean height was 179.2cm, s.d.
= 7.0cm. Mean weight = 78.2kg, s.d. = 8.3kg. Two of the volunteers were smokers.
Before the first trial each subject underwent a medical examination by an IOM physician to
ensure that they were physically fit enough to participate. At the start of each subsequent trial
the subject signed a health declaration form stating that they were still in good health.
15
Subjects attended the trials on different days but at the same time on each occasion. Each
trial was separated by at least 24 hours. Before each trial, thermistors were attached to the
skin at four sites using micropore tape. Three sites were selected outside the face mask while
one was selected within the mask. The following sites were chosen:
Site 1 (Forehead):
Site 2
(Left cheekbone):
slightly to the left of centre both. to. avoid being positioned over the
supra orbital vein and to avoid being positioned under the central head
BA face mask strap. It was positioned outside the face mask.
positioned to avoid the Angular artery and vein. This probe was
inside the face mask, but not compressed by any part of it. The
inhaled air from the BA cylinder was cold, and therefore had a
cooling effect on the facial skin. It is likely that this cooling effect
will be stronger than any rise in facial temperature caused by the
hood. It was hypothesised that no differences between hood or skirt
types would be identified at site 2 and it therefore acted as a control.
Site 3
(Lower left jawbone): on the face, but out of the face mask, and not compressed by any of
the BA mask straps. The site was easily identifiable, and therefore
replicable, and was also not over any veins or arteries. It was decided
that a probe should be placed on the subject's neck, so that it would
be covered by the hood both when it was worn up and when it was
round the subject's neck.
Site 4
(Midpoint neck
[back]):
selected to avoid the Common Carotid artery and the External Jugular
vein which run under the skin vertically below the ear.
The thermistors at sites 1 and 3 were covered in the 'hood up' condition but not in the control
(hood down) condition. Any local temperature differences caused by the wearing of the hood
should have been detected in the readings from these probe sites. The skin at site 4 was
covered by the fire hood in all the trials.
The aural thermistor was placed in the ear, and insulated from the ambient temperature
conditions using a cotton wool pad. ECG electrodes were attached to the subject's chest.
The subjects wore their rubber work boots, standard issue trousers and T shirt under a Bristol
Nomex Delta T tunic and overtrousers for the trials.
At the start of the trial, the subject sat resting outside the chamber for 10 minutes prior to
walking on the treadmill. The average ambient temperature outside the chamber during the
trials was 18.7°C (s.d. = 2.3°C). During this resting period the subjects wore a PASO BA
harness and BA cylinder. For all the trials the fire hood was worn around the neck during
this resting period and the collar on the tunic was worn turned up.
Following this rest period the firefighter put on the BA mask, helmet and gloves and, if
appropriate, the fire hood. He entered the chamber which had been preheated to
approximately 33°C and stood on the treadmill. He then walked at Skrnh'1 for 30 minutes
unless the following withdrawal criteria were exceeded.
16
If the subject's heart rate exceeded 80% of their age-predicted maximum (220 minus
age);
or
If the subject's core temperature rose above 39.0°C;
or
If the amount of air remaining in the BA cylinder became low, as indicated by the
whistle;
or
If the subject requested to be withdrawn.
Skin and core temperature, heart rate and wet and dry bulb temperatures in the chamber were
recorded by computer every 30 seconds. The temperature in the chamber was maintained at
33°+/-3°C. The humidity was not supplemented.
At the end of the test the subject left the chamber. After removing his fire kit he was given
a brief recovery period, then completed a questionnaire concerning the trial.
The
questionnaire differed slightly depending on the trial that had been undertaken (see Appendix
G).
2.8 Statistical Methods
The data collected for the study were examined in a series of tables and graphs. Statistical
analyses of the data from the observational trials and physical tests used the statistical methods
of multiple linear regression and analysis of variance. Analysis specific to each part of the
study are described in the relevant results section. All analyses were carried out using the
Genstat statistical software package (Genstat 5 committee, 1987).
17
3. RESULTS
3.1
Survey of Fire hoods within Brigades
3.1.1
In the autumn of 1992 when the survey was conducted more brigades issued neckerchiefs than
fire hoods. In England and Wales, thirty eight brigades out of a total of fifty two (who
completed the questionnaire) provided neckerchiefs and nineteen brigades provided fire hoods.
The most commonly used neckerchiefs were manufactured by Denne and W&D West. The
most commonly worn fire hood (12 brigades) was Mattinson's. Three brigades each used the
PUC fire hood and the Bristol E9 hood. Northern Ireland also provided the Bristol E9 hood
as well as the Denne neckerchief. In Scotland one brigade out of eight provided fire hoods
whereas four brigades used neckerchiefs supplied by various manufacturers. Overall, nine
brigades provided both fire hoods and neckerchiefs, eight brigades used neither, twelve
brigades used fire hoods only and thirty two used neckerchiefs only.
3.1.2
Operational firefighter questionnaire
This questionnaire included subjective questions about the effects of wearing fire hoods and
general opinion about them.
Response rate to firefighter questionnaire
A total of 1045 questionnaires were distributed to operational firefighters, of which 746 were
returned, giving a response rate of 71 %. Although nine of these were returned without any
brigade identification, they have been included in the analysis.
Using fire hoods
Eighty one per cent of firefighters were in favour of the concept of anti-flash hoods and
protective hoods although only 31% said they had been issued with any kind of protective
hood. Of those who had been issued with hoods, 93.4% were in favour of their use and
6.6% were not. Of firefighters who were issued with hoods 5.6% reported not getting
sweaty; 48.3% reported getting slightly sweaty and 40% reported getting very sweaty. Forty
one per cent thought the hood did not affect hearing; 51.7% thought the hood affected
hearing slightly; and 3% thought hearing was greatly affected.
When asked about interactions between hoods and other protective equipment and any
problems that were caused, 22.2% reported having problems. The commonest problem
related to difficulties with the breathing apparatus (BA) mask straps, which were reported as
catching on the hood as it was pulled into position and which were difficult to tighten once
the hood was fitted. One indicated that the fire hood obscured his vision and several referred
to difficulties in fastening their helmet over the fire hood and of it becoming unstable when
worn on top of a fire hood.
Almost one third (32.6%) thought that fire hoods isolated them from their environment with
suggestions that they may engender a false sense of security. Thirty per cent of firefighters
said they had received training in the use of the hood, 98% of these stating that this had
included the interaction between hoods and BA. Eighty four per cent reported wearing
18
protective hoods with BA. The main exercises during which hoods were used were BA
training, heat and smoke training, any incident with the possibility of flashover, any outside
exercises during winter, at their own discretion and where there was a risk of explosion,
either from cylinders or cars.
Sixty six per cent wore protective hoods during other operations such as incidents with intense
heat, barn fires, grass fires, RTA and all the time in winter. Many firefighters also stated
that they wore the fire hood as a neckerchief only. Given a free choice, 83% of those who
had been issued with a fire hood said they would wear it.
Additional comments were that hoods were good in cold weather; essential for all
firefighters; should be made more user-friendly; were very uncomfortable to wear when
wet; and should be made optional. Some firefighters stated that the hoods made hard work
in hot and humid conditions even more arduous and that they retained a lot of body heat.
3.1.3
Survey of external companies/international Brigades
Overseas Brigades
In the autumn of 1992 only Hong Kong Fire Service reported using fire hoods.
Australian, New Zealand and Gibraltar Fire Services did not provide hoods.
The
Airports
Of those who responded, Birmingham International Airport Fire Service were providing fire
hoods in 1992, London Heathrow Fire Service was evaluating both Martinsons and Bristol
fire hoods in July 1992. London Luton Airport Fire Service was also evaluating fire hoods
(not specified). East Midlands and Belfast Airports Fire Services were not using fire hoods.
Petrochemical companies
None of the petrochemical or other companies contacted, including Shell, Esso, BP and ICI
and the Offshore Fire Training Centre used fire hoods.
3.1.4
Injury reports
As part of an investigation of the degree of protection afforded by firefighters' clothing,
funded by the Home Office (Graveling et al. 1996) an accident reporting form was developed
and 51 brigades participated to some extent resulting in a total of 706 completed forms being
received. Of the reports received, 168 related to some form of burn injury (23.8%). It is
possible that, because of the nature of the study, some brigades may have encouraged their
staff to report only burn injuries and that consequently the recorded proportion of burn
injuries may be misleading.
Amongst the burn injuries, by far the most commonly reported sites of injury were the
unprotected parts of the head and neck. In more than half the reports multiple sites of burn
injury were identified, the ears being the most frequently identified site, followed by the neck.
From the descriptions received, the injury sites would have been covered by a fire hood.
19
3.2
Hoods Used for Trials
Most fire hoods were used throughout the project and those which became no longer available
commercially during the course of the project were replaced with others. Table 3.1 describes
each of the hoods used. With the exception of hood K, all were made from knitted (stretch)
fabrics.
3.3
The information obtained from the fitting trials carried out on each hood is presented below.
(a) Cairns and Brother Nomex fire hood
A total of nine firefighters carried out fitting trials on this hood. The most common problems
encountered (seven firefighters) were difficulties in fitting the hood, ranging from problems
with putting the hood on over the BA mask to difficulties in fastening the helmet once the
hood was in position. For most of the subjects these problems occurred during the second
trial condition involving the use of BA; however, two also had some difficulty fitting their
helmets in the non-BA condition. One subject felt that wearing the hood slightly restricted
his movement when tilting his head forwards to read his cylinder pressure gauge. Two
subjects said that the hood caused them some discomfort, one because the hood made him feel
too hot, and the other because it made his helmet fit too tightly. During one trial the facial
aperture of the hood revealed gaps around the mask.
(b) Cairns and Brother FBI fire hood
Of the seven firefighters who carried out fitting trials on this hood, two made no comment
or criticism of any kind. Among the remaining five the most common problem was the poor
fit around the BA face mask in the second trial condition and gaps frequently appearing as
a result. The other subjects experienced minor difficulty when fitting the hood over their BA
mask; the hood not moving with their head; and problems with the hood yoke pulling out
of the tunic.
This hood became badly misshapen following laundering and it is likely that this may be at
least partially responsible for the frequency with which gaps were reported to appear around
the BA face mask.
(c) Diktron Developments Nomex III fire hood
Ten firefighters carried out fitting trials on this hood. At a very early stage it became
apparent that this hood was not suitable for use with BA as the facial aperture was
insufficiently large and therefore it was impossible to fit the BA mask correctly.
Consequently the results given below were obtained from fitting trials conducted in the
condition without BA.
Nine subjects reported that gaps appeared around the bottom of the hood yoke during
movements involving tilting of the head. Two firefighters complained of problems with their
helmets moving whilst wearing the hood, and one felt that the hood caused him some skin
irritation.
20
(d) Mattinsons 'Protekta' fire hood
Half of the fourteen firefighters who used the hood made no comment or criticism of any
kind. Among the remaining seven the most common complaints were about fitting
difficulties, particularly in the condition with BA. Five subjects reported having problems
either fitting the hood when wearing the BA mask or fastening the helmet once the hood was
in position. Other comments recorded were: the hood was irritating to wear (two subjects);
the hood was uncomfortable with a helmet which pushed the hood's seams into the wearer's
scalp (one); and the hood moved on his head during the without BA fitting trial condition
(one).
This hood was familiar to some of the firefighters participating in the fitting trials because it
is widely used by brigades that currently issue fire hoods.
(e)
PUC Kermel/Viscose fire hood
A total of ten firefighters carried out fitting trials on this hood. Two made no comment or
criticism of any kind. As for hood D, among the remaining eight the most common problems
encountered were fitting difficulties, almost entirely in the 'with BA' condition. Five of the
subjects reported having these difficulties chiefly when attempting to fit the hood over their
BA mask although fastening the helmet strap also proved difficult for some. Other comments
recorded were: gaps between the BA mask and the fire hood (two subjects), the facial
aperture in the hood was slightly large (one), and the hood caused skin irritation probably
related to allergy to wool (one). Interestingly, three subjects volunteered that this hood was
more comfortable than the Mattinsons hood they currently used.
(f/g) Tempo Uno/Uno L fire hoods
Among the thirteen using this hood, five reported that the hood caused itchiness which
provided a source of distraction. Other problems were also reported with fitting the hood
when wearing BA (four subjects); gaps appearing in the area where the hood's yoke splits
and exposing skin (four subjects); restriction of some movements (two); discomfort as a
result of the hood causing the helmet to fit too tightly (one); vision restricted by the hood
in the condition without BA; and an adverse effect on security of the helmet fit.
(h) Warm 'n Dry kermel/viscose fire hood
Of the fifteen using this hood only two made no comment or criticism of any kind. Among
the remaining thirteen the most common problem (nine subjects) was that the hood, having
a short yoke, failed to provide adequate protection of the neck and left skin exposed. Five
complained of fitting problems with this hood, particular when wearing BA and two
complained that their helmets were insecure as a result of wearing the hood. Six subjects said
the hood caused skin irritation and one reported that his helmet became uncomfortably tight
when wearing the hood.
This hood was unique amongst those tested in the fitting trials in not having a yoke, probably
resulting in the large number of problems with exposed skin during the trials on this hood.
It should however be noted that this hood had not been subjected to normal commercial
design procedures having been made up at short notice because of interest in the fabric
amongst some brigades.
21
(i) Bristol E9 anti-flash hood
A total of ten firefighters carried out fitting trials on this hood. As the design and method
of use for this hood were very different to those of the other hoods evaluated, the results were
also different. The hood was only evaluated with BA being worn.
The most common problem reported (six subjects) was that gaps appeared around the hood's
skirt, particularly when the wearer was required to lift his head or look upwards. This
movement was at least partly due to the restriction on vision imposed by the hood visor,
which forced the wearer to lean his head back more than usual in order to see upwards. Five
of the participants felt that wearing the hood restricted all-round or peripheral vision to a
varying extent, one of whom felt that it would make it difficult to read his cylinder pressure
gauge in a smoky environment and would probably increase reading time under normal
conditions. Six subjects had problems with fitting the hood, particularly over helmets with
visor attachments, but also over their BA masks. Four subjects said the hood restricted
movement by catching on the BA mask demand valve, which also caused the hood to twist
out of position. One subject felt the weight of the hood caused his helmet to tip forwards
causing some discomfort; and another suggested that the noise generated by the hood rubbing
on his tunic and other equipment could reduce his hearing sensitivity.
3.4
Subjective Responses to Wearing Fire Hoods During Training Exercises.
3.4.1
Introduction
These trials examined two main issues in relation to fire hoods. The first was to establish the
views and attitudes towards hoods in general, the second was to determine the reactions of
experienced firefighters to the specific hood which they had just been wearing.
3.4.2
Attitudes to hoods
Seven different hoods were evaluated during these trials. Table 3.2 summarises attitudes
before the subjects wore the hoods allocated to them as it was considered that these attitudes
might influence their responses to the trial hoods. The results do indicate variations in
attitudes amongst the participating groups. Mostly, however, they indicate that the majority
of firefighters (58% overall) considered that fire hoods provided essential additional
protection. However, a small majority (55%) also considered them to create a loss of
awareness of the environment. On the specific issues of thermal and auditory isolation almost
equal numbers (36%) regarded them as having an adverse effect.
3.4.3
Findings for individual hoods
Because of the poor response from the initial distribution of fire hoods and questionnaires to
brigade training centres there was a marked imbalance in the number of comments received
on different hoods. Consequently, to avoid distorting the results these returns were not used
in the analysis given below which are therefore each based on the responses of twelve
firefighters.
22
Cairns and Brother (Nomex)
Two firefighters encountered problems with their BA face mask when wearing the hood. One
of them mentioned that when he pulled the hood over his mask it tended to pull the mask off
his face. The second firefighter found that he could not get a good seal on the mask when
it was worn with a fire hood. None of them encountered any problems with the hood and
helmet interacting. The majority found that the hood fitted snugly around the BA mask.
Only two found that gaps developed between the hood and the mask. One found that the
peaked material at the front of the hood kept dropping down over the visor and interfering
with his vision. He also found that he was unable to get a snug fit around the mask from his
temples down to his jaw, because the edges of the hood curled up. The second firefighter
reported that the hood did not fit around the edge of the mask at any point.
All of the firefighters assessing this hood found it easy to put on. Seven found it very easy
and five quite easy to put on. None of the firefighters found that the hood greatly increased
their sweat rate but eight did find that it slightly increased sweat rate. Seven of the
firefighters felt slightly hotter when wearing a hood, while two felt slightly cooler. Only two
believed that the hood slightly reduced their ability to hear. The remaining ten considered
that the hoods had no effect on their hearing. All but one of the wearers found the fire hoods
comfortable to wear.
All of the firefighters said they would be happy to wear a fire hood for firefighting.
However, two of them would not have wanted to wear this particular hood because they both
considered it to be too thick.
All of them agreed that their ability to carry out their exercises was unaffected by wearing
a fire hood.
Two firefighters could not think of any firefighting situation when they would choose to wear
a fire hood and all of them agreed that the decision to wear a fire hood should be left to the
discretion of the individual firefighter.
Cairns and Brother (FBI)
After donning the fire hood in question two firefighters found that the fire hood caused
problems when worn with the BA mask. One found the hood too small and short at the neck
leaving skin exposed and he also had difficulty in placing the hood over the mask straps
without causing air loss from the mask. The second man also found that his hood caused his
mask straps to loosen when it was being pulled into position. None of the firefighters found
that hoods caused any problems with the helmet. Two of them did not get a snug fit around
the visor of the mask. One explained that his fire hood was too loose at the top of the visor,
creating a gap.
Two of the firefighters found it difficult to put on the fire hood. Observations suggested that
the problems arose from pulling the hood over the mask straps. Half of the remaining
firefighters found the hood easy to wear and the other half found it very easy to use. After
the exercise, eight firefighters thought that wearing a fire hood slightly increased their sweat
rate, whereas one thought that wearing a fire hood slightly reduced it.
None felt isolated when wearing a hood. Three thought that wearing a hood allowed them
to get closer to a fire. However, a further six firefighters did not find this to be the case.
23
None of them agreed with the statement that 'wearing a hood made me feel less confident
about the state of the surrounding environment' and all agreed that wearing a hood did not
affect their ability to carry out a task. All said they could think of situations in which they
would elect to wear a hood. However, most (ten) agreed that the decision to wear a fire hood
should be left to the discretion of the individual.
Diktron
After donning the test hood three found that they could not get a snug fit between the BA
mask and the hood, whereas none had any difficulty in using the fire hood with their helmet.
All of the twelve firefighters found the hood easy to put on, with none of them finding it very
easy. Seven of them found that wearing it had no effect on their sweat rate, although five
found that their sweat rate did increase, two of these greatly.
Five firefighters said that wearing a fire hood had no effect on how hot they felt during the
exercise whilst two felt slightly cooler with a hood on. The remaining five all felt hotter, two
of these much hotter, when wearing a hood. All of the firefighters found the hood
comfortable to wear, five of these finding it very comfortable. For seven wearers the hood
had no effect upon their hearing ability, whereas the remainder thought that hoods did affect
their hearing.
Eight out of the twelve agreed that they felt better protected wearing a hood, while only one
firefighter disagreed. One felt too isolated when wearing a hood, whereas ten felt unaffected.
Most of the firefighters did not hold an opinion on whether or not a fire hood allowed them
to get closer to the fire. Four of the five who commented believed that it did reduce their
confidence in the state of the environment. No firefighters felt that their ability to carry out
the exercise was affected by the wearing of a fire hood. Four firefighters could not think of
any situation in which they would choose to wear a fire hood although the remaining
firefighters could. Eleven out of the twelve firefighters stated that it should be up to the
discretion of the individual firefighter to decide whether or not to wear a fire hood.
Martinsons
After fitting the hood in question, three of the firefighters said that they had found the hood
to be too small when worn with their BA mask, whereas none had any problems with the
helmet when it was worn with the fire hood. One firefighter found that the hood was tight
around the top of the mask. Seven found it easy and four very easy to put on. After the test
exercise half of the firefighters found that wearing a hood had no effect on sweat rate, while
the remaining six thought that the hood slightly increased it.
Half of those tested thought that wearing a fire hood had no effect on how hot they felt, two
felt slightly cooler whilst a further four felt slightly hotter. Ten said there was no effect on
their hearing when wearing the hood and two thought that their hearing ability was slightly
reduced. None of them had any problems in using the fire hood with other equipment.
Of the ten firefighters who commented on the ear sections all said they were correctly aligned
over the ears. Nine of these thought the perforated ear holes were a useful feature in terms
of increasing the audibility of sound.
24
Eleven of these firefighters felt much better protected wearing the hood. The only one who
did not feel this way also did not want to wear a hood. Only one firefighter felt that the fire
hood made him feel too isolated. Four thought that wearing the fire hood allowed them to
get closer to the fire, although more believed the opposite. Three felt less confident about
their environment when wearing hoods, although the other nine were as confident as usual
of their environment and were able to carry out their exercises completely unaffected. Eight
firefighters could think of situations where they would choose to wear fire hoods, although
two could not. However, ten agreed that the wearing of a fire hood should be at the
discretion of the wearer.
PUC
With this fire hood, one found that, the mask straps loosened when pulling the hood on.
Another found that it took extra time to don his mask. One of the wearers had a problem
with his helmet when worn with the hood, which caused the helmet to be too tight. All of
them found that the hood fitted snugly around the mask. One of the firefighters found it quite
difficult to put on the fire hood, although the rest found it either easy or very easy. After the
exercise, four of the firefighters said that wearing the fire hood had no effect on their sweat
rate, although the rest did notice an increase in sweat rate, one noticing a great increase.
Four firefighters did not notice any change in how hot they felt when wearing the hood. Four
felt slightly hotter, but four also felt cooler, one of whom felt much cooler. All of them
found the fire hood comfortable to wear, with half of them finding it very comfortable. Four
of the firefighters thought that it slightly reduced their ability to hear, although eight reported
no effect.
Half of the firefighters stated that they felt better protected as a result of wearing a fire hood,
although three others did not feel better protected. Three other wearers felt isolated when
wearing the hood. Four firefighters found that they could get closer to the fire when wearing
a hood than when not wearing a hood. Two firefighters found that they felt less confident
about the state of their environment when wearing a hood, although the other ten were
unaffected by the use of the hood.
All of the firefighters agreed that their ability to carry out the task was unaffected by the use
of a fire hood. One firefighter said he could think of no situation in which he would choose
to wear a hood, whereas nine others could.
Most of the firefighters agreed that the decision to wear a fire hood should be left to the
discretion of the individual, with only one dissenter.
Heathcote
Three firefighters found that, because the fire hood was too small and tight, donning it caused
the mask to lift off the face causing air leakage.
However, none of them found that using a fire hood interfered with their helmets and all
reported that the hood fitted snugly around the face mask.
Two firefighters regarded the hood as difficult to put on, whilst seven found it easy, and three
very easy. Three firefighters found that wearing a hood had no effect on their sweat rate, one
that his hood reduced it slightly, and eight firefighters found that it increased slightly. Four
firefighters found that wearing a hood did not affect how hot they felt, three felt slightly
25
cooler and five felt slightly hotter.
Only one firefighter found the hood uncomfortable. Most found it comfortable, three finding
it very comfortable to wear. Three firefighters said it slightly reduced their hearing ability
while the other nine did not notice any effect.
All of the firefighters agreed that they would be happy to wear a fire hood for firefighting
operations, although one firefighter said he would not be happy to wear this hood because it
was too tight and would be difficult to remove in a hurry.
None said that they felt less well protected as a result of wearing a hood. One firefighter
thought that he was too isolated during the exercise because of wearing a hood, although the
rest of the firefighters did not feel isolated. Five did not comment on how close they got to
the fire when wearing a hood. Of the seven that did comment, three thought that they could
get closer to the fire, while four thought that they could not. Only one felt less confident
about his environment when wearing a hood, although ten said that the hood had no effect
on how confidently they could assess the environment.
Eight firefighters stated that their ability to carry out their tasks was unaffected by wearing
a fire hood, although three thought that their ability was reduced. Only two firefighters could
not think of a situation in which they would wear a fire hood. Most of the firefighters (ten
of the twelve) believed that the decision to wear a fire hood should be left to the discretion
of the individual firefighter.
Warm 'n Dry
After fitting the hood in question, six of the firefighters encountered problems with the BA
mask. Three of these found that, because of the tightness of the hood, it loosened the mask
straps, breaking the seal of the mask when the hood was being pulled up onto the head.
Another found it difficult to tighten the straps once they had been loosened, whilst another
had problems in getting a good seal. None of the firefighters had any problems with the hood
interacting with the helmet. Only one did not find that the hood fitted snugly over his head;
it was too small and did not cover his head properly, causing a gap between the top of the
fire hood and his face mask.
Most of the firefighters found the hood easy to put on; however, two firefighters found it
difficult, one of whom found it very difficult.
Regarding sweat rate, four reported no effect, three a reduction and five an increase, of
whom two reported this increased greatly; whereas three felt hotter, three slightly cooler and
six noticed no such effect when wearing this fire hood.
One firefighter did not believe that he was better protected when he wore this fire hood,
compared to nine others who thought they were. No firefighter said that the fire hood made
them feel too isolated. Only half commented on whether or not the hood allowed them to get
closer to the fire. Of these, four said that wearing a fire hood did not allow them to get
closer. Only two firefighters said that wearing a hood made them feel less confident about
the state of their surroundings.
All of the firefighters who commented agreed that their ability to carry out a task was
unaffected by wearing a fire hood. One firefighter stated that there was no firefighting
26
situation he could think of that would make him choose to wear a fire hood. Nine others
could think of situations where they would. Most of the firefighters (nine) agreed that the
decision to wear a fire hood should be left to the discretion of the individual firefighter.
3.4.4
Summary of comments
Although most firefighters had some criticisms of the fire hood they wore, the majority
commented reasonably favourably and stated that they would be willing to wear a fire hood.
Most appeared to moderate their attitudes somewhat on actually experiencing the use of a
hood. For example, although before the trial most of those who were subsequently to wear
a PUC hood commented unfavourably on thermal and auditory isolation, these responses were
reduced after the trial. Nevertheless, a significant minority in each case retained beliefs in
increased thermal isolation and auditory impairment.
A majority also reported feeling more hot and sweaty as a result of wearing their fire hood,
although the extent of comments varied between hood types. The trials were not established
to select a particular preferred hood and most had their proponents and detractors. However,
a number of style/design issues were identified which will be discussed later.
3.5
Observational Trials
3.5.1 Data and statistical analysis
The observational trials were completed by 55 firefighters, each of whom was randomly
allocated either to the control group (no fire hood) or to one of three fire hood groups (skirt
only, hood only, hood plus skirt). Table 3.3 shows the distribution of the firefighters by
brigade and fire hood group and shows that the two factors are not independent (not all hoods
were used by all brigades). For two brigades, very few firefighters participated in the trials three individuals from brigade 3 allocated to only two different fire hood groups and five
individuals from brigade 4, all of whom used fire hoods with skirts only. One firefighter,
from brigade 5 wearing a fire hood with skirt only, was omitted from the analysis because
of missing data.
Times taken by each individual to complete each of four zones in the fire house were
recorded. The total time taken to complete all four zones was calculated. Time taken in zone
5 was not included since a number of the participants were unable to complete the trial and
had to be pulled out from this final zone. The temperature of each zone was also recorded
for each individual trial.
The data were examined using multiple linear regression methods and associated analysis of
variance tables. Time in each zone was adjusted for temperature in the zone. Time in each
zone was transformed to the log scale prior to analysis as preliminary investigations showed
that models fitted on this scale provided a better fit to the data.
Time taken in each zone was compared between controls and the three fire hood groups. The
interaction between fire hood group and temperature was also examined to see if any
differences between fire hood groups varied by zone temperature (eg if differences between
fire hood groups were more pronounced at hotter temperatures). Differences in technique
between brigades were observed during the trials and, because the effect of brigade was not
independent of fire hood group, differences between fire hood groups were also examined
27
after adjusting for brigade differences. The level of confounding between these two factors
means that it was not always possible to distinguish the effect of one or other of them.
In each of the summary tables from the multiple regressions (Tables 3.5 to 3.7) the regression
coefficients attributable to brigades are referenced to brigade 1. Consequently, brigade 1 does
not appear as a term in any of these tables. The regression coefficient is the value for 'b' and
the intercept constant is the constant 'a' in the linear regression equation y = a + bx.
3.5.2 Time to complete exercise
The times which each subject spent in each of the first four designated zones are presented
in Table 3.4. Time taken to complete zone 2 was of particular interest since this was the
hottest of the zones, and the zone in which differences between fire hood groups were most
likely to be found. Results from the statistical analyses of the time in zone 2 are shown in
Table 3.5. No overall differences were seen between fire hood groups (model 1), however
there were substantial variations in the time taken by different brigades. Firefighters from
brigades 2, 3 and 5 completed this zone significantly faster; taking around 75% of the time
taken by firefighters from brigades 1 and 4 (ratios of estimate to standard error -2.22 [brigade
2]; -1.72 [brigades]; -2.59 [brigades]). These brigade differences were still apparent after
adjusting for differences between fire hood groups (-1.81; -1.98; -2.14, model 3).
There was some evidence that the differences between fire hood groupss varied with
temperature (the Temp. Hood group term in model 4) with firefighters wearing hoods and
skirts tending be slower in hotter temperatures compared to the controls (ratio 2.06, model
4). This effect was less apparent after adjustment for brigade differences (ratio 1.54 model
5).
Firefighters wearing hoods only took significantly less time than the controls to complete zone
3 (ratio -2.87 model 1; table 3.6). This difference is still apparent when differences between
brigades are also adjusted for (ratio -3.46 model 3). There is no evidence that these
differences between fire hood groups vary with the temperature of the zone (models 4 and
5). No significant variation between brigades is apparent in this zone (model 2).
Similar analyses of the time taken to complete zone 1 showed that there were no significant
differences between fire hood groups or brigades (results not shown), while firefighters in
brigades 4 and 5, were substantially slower than the controls in completing zone 4 (ratios
2.08 [brigade 4]; 3.12 [brigade 5] model 2; table 3.7).
A combined analysis of the times in each zone for each individual, using the REML facilities
of the Genstat statistical package, confirmed that the largest variations occurred between zones
(table 3.8) and in the interaction between brigades and zones showing that there were
differences between brigades which varied across zones.
3.5.3 Subjective awareness of temperature
During the exercises, in three of the zones, participants were asked to report what they
thought the environmental temperature was. The purpose of this was to determine what
effect, if any, wearing a fire hood or other device had on temperature perception. The mean
results for these, together with mean values for the actual temperature at the time, are given
in Table 3.9.
28
The data were analysed in a similar way to that described above, adjusting the results for any
influence of the actual temperature at the time. The analyses examined the effects on
awareness of temperature of brigade and fire hood or other device worn. Preliminary
analysis showed that using a logarithmic transformation for the temperature data yielded a
better fit to the model.
In the hottest zone, zone 2 (table 3.10), the perceived temperature was significantly influenced
by the actual temperature (ratio 2.28, model 1). Firefighters wearing skirts only tended to
perceive lower temperatures than the controls (ratio -2.23, model 1), however this difference
was no longer apparent once the significant differences between brigades had been taken into
account (model 3). Firefighters from brigades 2 and 5 perceived lower temperatures than
those from other brigades. In the first zone brigade 5 and, to a lesser extent, brigade 2 again
perceived lower temperatures (model 2, table 3.11) and there was also a significant interaction
between actual temperature and fire hood group (model 4). This was largely attributable to
those wearing fire hoods only, whose estimates of environmental temperature rose faster than
other participants with increasing actual temperature. In zone 4 (table 4.12), where the actual
temperature fell, estimated temperature remained relatively high (and in some cases increased
slightly). As for zone 2, an apparently lower perception of temperature by those wearing
skirts only was not apparent after adjustment for the effect of brigade (where lowest
temperatures were once again perceived by individuals from brigades 2 and 5).
3.5.4
Behavioural responses
Each firefighter was observed during the exercise and rated on four key behavioural elements:
gauge checks; door entry procedures; stair safety procedures; and search thoroughness.
These ratings were classified by training centre safety staff and an independent observer as
'good' or 'poor' and the results are presented in Tables 3.13 to 3.18.
After the completion of the exercise, as a further indication of the quality of their view of the
scenario, they were asked during their debriefing to produce a sketch plan of the two floors
of the search location. This is apparently standard practice in some brigades in order to
provide briefing information for any further teams to be committed.
Statistical analyses of these results showed that most of the variability (and the only
differences of any statistical significance) were attributable to differences between brigades.
For example, only one brigade regularly included sketch production in their training. None
of the experimental conditions had any consistent effect in any of the behavioural indices
studied.
3.5.5
Subjective responses
In the final part of their debriefing, participants were asked a series of questions regarding
their reaction to the hood and/or skirt just worn. The results were as follows:
Isolation
Seventy nine percent did not feel isolated. Of the remaining 21 %, most wore both fire hood
and skirt (50%). Fewest, (12'/2%) wore just a helmet skirt.
29
Temperature awareness
Fifty six percent felt that their temperature awareness had been reduced. This belief was
expressed significantly less by those wearing a helmet skirt (14%) than those wearing a fire
hood or both fire hood and skirt.
Hearing ability
Twenty four percent considered that their hearing ability was impaired by wearing a helmet
skirt and/or hood. Only a few (17%) just wore skirts and most (50%) wore both.
Communication
Just over one in ten firefighters (10.5%) considered their fire hood and/or helmet skirt to
interfere with communication. Surprisingly, more who wore just a fire hood expressed this
view than either of the other two groups.
Sound location
Sixteen percent of firefighters indicated that they considered their fire hood or fire hood plus
skirt to interfere with sound location. These were evenly divided between the two groups
with none of those who wore just a helmet skirt expressing this view.
Level of protection
Seventy two percent of firefighters considered the level of protection provided to be about
right. Of the others, 7% regarded it as too little and 21% too much. The majority of the
latter group were amongst those who wore fire hood and skirt together.
Finally, despite all the criticisms implicit in the above responses, 84% of participants thought
that fire hoods or skirts were a good idea with a slight majority of these amongst those who
wore just fire hoods.
3.6 Physical Tests
3.6.1 Radiant heat transfer of fire hoods
Table 3.19 shows the average length of time taken for the temperature of the thermistor
behind the fabric to rise by 25°C and the standard deviation between the five test samples.
From this, it can be seen that the length of time it took for the temperature of the copper disc
to rise by 25°C varied considerably between the different materials from an average of 32.63
seconds to 61.58 seconds. Four of the fabrics produced acrid smelling fumes on exposure
to the heat source. Five of the fabrics were scorched by the heat. Most of the samples of
hoods were reasonably consistent, the exception being hood 6, different samples of which
demonstrated a substantial variation in performance.
For comparison, tests were conducted using the fabric of the E9 anti-flash hood. Firstly,
measurements on a small sample of volunteers showed the typical distance between the hood
when worn on the helmet and the skin was approximately 10cm. Then the radiant heat test
30
was assembled with a 10cm air gap between the fabric and the heat sensor. This yielded very
slow rates of temperature increase, for example, after 45 seconds the temperature increase
was an average of 5.2°C (+ 0.19°) and after two minutes the temperature had only increased
by an average of 15.3°C (± 0.28). As would be expected, comparable figures for tests
incorporating both the E9 fabric and a fire hood (Cairns and Brother Nomex) were even
lower with average temperatures after 45 and 120 seconds of 1.1°C (± 0.12°) and 4.1°C (±
0.27°) respectively.
3.6.2
Closeness of fit
Measures obtained on the standard size model head for the degree of stretch for each fabric
and the amount of loose material around the neck are shown in Table 3.20 together with
subjective observations of the closeness of fit. They show quite a wide range of variation in
both parameters between the different hoods.
3.6.3
Oven test/heat build-up tests
The surface temperatures on top of the standard size model head under a series of
combinations of fire helmet (with or without skirt) and fire hood were recorded as described
in section 2.5.4. The results are given in Tables 3.21 and 3.22 for the two test conditions
used. Both tests show a tendency for the helmet skirt to increase the temperature under the
helmet.
3.7
3.7.1
Audiometric tests
Each helmet or fire hood was tested at least six times to determine the degree of noise
attenuation which they produced. The results from this are shown in Table 3.23.
The results show that, at most frequencies, neither helmets nor hood have any meaningful
effect on sound levels at the ear. The figures shown should be interpreted against the fact
that the minimum detectable change in noise level is 3 dB. There is some indication that the
helmets create a small amount of resonance at around 2kHz resulting in an increase in noise
levels at the ear compared to outside levels.
3.7.2
Sound location tests
None of the volunteer firefighters had any trouble with the preliminary test, conducted
without wearing a fire hood. No errors of sound location were made in these tests and so the
results are not tabulated. Each hood was tested on three separate firefighters. Eight different
hoods were included in this testing, being hoods A to G from table 3.1, together with hood
J. Throughout all trials and all presentations (a total of 96 presentations) two signals were
wrongly identified. These errors were both made by the same subject wearing the same
hood. (Hood B, Cairns and Brother FBI). No other subjects wearing that hood experienced
any problems and that subject made no further errors with other hoods.
In comparison, more location errors were recorded in trials wearing a conventionally shaped
helmet with a protective neck curtain and with the close-fitting Gallet helmet.
31
The results for these tests are given in Table 3.24. From this, it can be seen that typically
one firefighter made errors with most combinations, although the most enclosing system
(Gallet with lining and collar) resulted in three of the four firefighters who wore this making
mistakes in locating the direction from which sounds were coming.
3.8
Physiological Load Imposed by the Hoods.
3.8.1
Physiological data
The experimental design involved eight firefighters each performing ten tests. During the
experimental period, one subject had to withdraw due to an injury unconnected with the tests.
The two trials not completed by that subject were those involving the Gallet helmet. All data
sets for these tests are therefore based on the results for seven subjects. The statistical
analysis used analysis of variance methods adjusting each physiological variable for the initial
value and environmental temperature.
Mean final heart rate
Heart rate data records, adjusted statistically for differences in initial heart rate and
environmental temperature were used to determine final heart rates for each subject for each
test. Mean values for these are given in Table 3.25. Statistical analyses showed no
comparisons to be significantly different at the conventional significance level of p = .05.
There are no consistent patterns or trends with one hood yielding a (slightly) higher mean
when worn up and the other when down.
Mean final aural temperature
Aural (ear canal) temperature data records, adjusted statistically for aural differences in initial
aural temperature and environmental temperature were used to determine final aural
temperatures for each subject for each test. The mean values for these from all subjects are
given in Table 3.26.
The results showed very small differences between different tests with only 0.29°C separating
the lowest from the highest. Two comparisons were statistically significant (p = .05). These
were the comparisons between the two hoods (pooled data - hood up and hood down) and the
comparisons between the hood up and hood down pooled data with various forms of skirt.
However, these results should be interpreted with caution as the differences are
physiologically very small and because, with multiple statistical comparisons, some significant
findings at this level would be expected due to chance (1 in 20).
Skin temperatures
Skin temperature records from the four selected sites, adjusted statistically for differences in
initial temperature and environmental temperature were used to determine final skin
temperatures for each subject for each test. Mean values for these are given in Tables 3.273.30.
The result for site 1 (forehead) (3.27) shows a statistically significant effect when a hood was
worn down compared to a hood worn up (pooled data for both hoods, p = .01). Thus, the
mean for the hood down conditions was 0.67°C higher than the hood up conditions.
32
For site 2 (left cheekbone) (3.28) no comparisons were statistically significantly different.
Comparisons of the data for site 3 (lower left jawbone) (3.29) showed one comparison, that
for the Gallet helmet with or without a skirt to be significant at the p = .05 level the mean
values differing by 0.95°C. This was in the expected direction, the skirt producing higher
temperatures.
Finally, for site 4, (the mid-point of the back of the neck) (3.30), three comparisons were
significantly different. These were the pooled (hood-up plus hood down) data for the two
types of hood (p = .01); the no skirt condition is the pooled (short plus long) skirt
conditions (p = .05) and the Gallet helmet with or without a skirt (p = .01). The PUC hood
produced skin temperatures 0.7°C higher; skirts produced skin temperatures 0.37°C - 0.53°C
higher; and the Gallet helmet skirt produced skin temperatures 1.32°C higher.
3.8.2
Subjective data
Two sets of subjective data were collected. The first were of perceived body temperature,
the second supplemented earlier data on the case of putting on a fire hood (with BA);
movement of the hood etc. when being worn; restriction of movement; and comfort during
the trial.
Perceived temperature
Perceived temperature was recorded on a five-point scale. 1 : cool; 2 : neither hot nor cold;
3 : warm; 4 : hot; and 5 : extremely hot. This was obtained both for the whole body and
for the head. Mean value for these are shown in Table 3.31.
A non-parametric statistical test (Friedman test) was conducted on these sets of data but no
statistically significant differences were identified. With the exception of one mean value,
which just fell outside, all means were within the range between warm and hot, although none
actually achieved the latter score of 4.0. Correlation analyses revealed no significant
correlations between skin temperatures (any site) or core temperature and these ratings.
However, there was a significant positive linear correlation between perceived head
temperature and heart rate.
Although not statistically significant, the mean subjective ratings do generally show a trend
in the expected direction. Thus, for four of the five comparisons, the mean perceived whole
body temperature is marginally lower for each control condition than its respective test
condition. The differences are both more consistent and generally more pronounced for
perceived head temperature although the results are again not statistically significant.
Questionnaire responses
There was only a single instance of any reported difficulty in putting on either fire hood, none
reporting problems with their BA face mask loosening. Two reported minor difficulties with
a conventional helmet and skirt and five reported minor difficulties with the Gallet helmet and
skirt, one of these also reported major difficulties with this helmet without a skirt. Four
subjects reported minor difficulties in attaching the Gallet face mask and one reported major
difficulties. This was however a relatively novel mask for all subjects.
33
Once the hood, helmet and mask were fitted, no subjects reported being aware of either the
hood or the helmet moving. There were however four reports of the BA face mask moving,
twice with the fire hood worn round the neck and twice in the Gallet and skirt condition.
No gaps developed which would have left skin exposed between the face mask and the hood
and only one subject reported any restriction of movement in any trial. This was with the
Gallet helmet.
34
35
4. DISCUSSION
4.1
Survey Responses
Over the period that the study has been carried out there has been a shift in the neck/head
protection used by the brigades away from neckerchiefs to fire hoods.
In the Autumn of 1992 although eighty per cent of firefighters were in favour of the concept
of hoods only thirty per cent were issued with them. However of those that were issued with
them ninety three per cent of wearers thought they were beneficial. This strongly suggests
that once firefighters are familiar with the wearing and use of hoods any concerns they have
about wearing them are markedly reduced.
Even though the fire hoods were accepted as beneficial they were still perceived to be sweaty
and uncomfortable to wear and also were thought to reduce the wearers' ability to hear. The
design of the hoods caused many problems by being too tight, loose, short or itchy. They
were considered to be particularly unpleasant to wear when wet. It was thought that this
could also lead to scald injuries during a flashover incident.
Very few airport/international brigades wore hoods in the Autumn of 1992 and none of the
petrochemical companies contacted wore hoods, although usage of hoods has increased since
1992 in parallel with the national fire service.
The reports on burn injuries, collected as part of the project on the degree of protection
provided by firefighters' clothing, provided clear evidence that, where the clothing cover
ended, the protection provided diminished dramatically. From the accumulated statistics there
is no doubt that a great deal of pain (and possibly disfigurement) could probably be prevented
by the regular use of fire hoods. Many of the injuries occurred in relatively commonplace
situations rather than flashovers and, reading individual reports, it becomes apparent that
firefighters were often not aware that they had incurred a burn until they came out of the
incident. This lack of awareness is borne out by the findings of the Behavioural Trials
(discussed below, section 4.3) that wearing a fire hood did not significantly affect the ability
of firefighters to judge temperature and both contradict the common assertion that the ears
act as the vital sensor to indicate a need for withdrawal.
4.2 Subjective Responses to Fitting and Wearing Fire Hoods
This section discusses the findings from two sections of the results.
Fire hoods are intended to be relatively close fitting. Inevitably therefore, particularly as they
are currently only manufactured in a single size, some firefighters will consider them to be
too close fitting, or too tight to put on. Moreover, a number of these hoods were not
necessarily designed for firefighters and, in particular, were not designed to be worn with
BA. As a consequence, a number of the sizing difficulties were probably attributable to the
additional bulk created by needing to don the hood over BA face mask straps. It is of course
important that firefighters fit the hood in this fashion as putting the straps over the hood could
compromise the face mask seal.
36
Another problem which occurred and was particularly apparent with some types of hood, was
also related to the BA face mask. In these cases, the opening in the hood was not always
compatible in size with the face mask visor and surround. With one style, the opening was
too small and trials of this hood had to be discontinued. With some others however, the
opening was sometimes too large, and small areas of skin would be exposed between the
edges of the face mask and the hood, thereby degrading the protection provided. This is an
important finding, not just because of the risk to the wearer but because compatibility between
different forms of PPE is a requirement of the PPE Regulations (HSE 1992).
A further sizing issue related to the length of the hood. The better hoods were designed so
as to be long enough to extend well down onto the chest and neck/back region, frequently
being styled to form a spreading yoke. Properly fitted, with this yoke spread out under the
tunic, these provided excellent coverage with no reports of hoods riding up or of gaps
forming at the neck.
Less well styled hoods had a number of deficiencies. These included a yoke which was too
short; the head section too short so that the division for the yoke was not always covered by
the tunic collar (allowing gaps to appear); no yoke shaping at all (making it more likely to
ride up in use); or, in one case, the whole hood was much too short so that neck protection
was inadequate.
There were isolated complaints about the fabric of some hoods causing minor irritation. This
was most marked in one subject who attributed his problems to his wool allergy (the hood
having some wool in its fabric composition. The nature of the inner surface of the hood
fabric is clearly an important factor here.
Once the hood was fitted over the BA straps, the fire fighter had to fit his helmet. This often
required some adjustment of the head band to allow for the bulk of the hood (as well as the
BA). Some firefighters reported problems with this, although this was possibly as much a
function of the style of helmet which they had as brigade issue. There were some instances
of complaints that bulky seams on the fire hoods were being pressed into the scalp and some
complaints of discomfort as a result.
With some hoods, firefighters considered that their helmet was not so well fitting as without
the hood, leading to concerns that it was unstable on the head. As with the comment above,
this was probably determined by the design of helmet worn by these individuals although this
factor was not examined systematically. Although thickness of fabric per se did not seem to
be a determinant it is possible that the use of multilayered fabrics might have an adverse
influence. Clearly, as with the hood/BA face mask problems described earlier, this is another
instance of where compatibility between different forms of PPE should be ensured. Unless
the interacting items are made by the same manufacturer the responsibility for ensuring
compatability under these Regulations rests with the employer. However, under parallel
Regulations concerning the manufacture (rather than the use) of PPE (Council Directive
89/686/EEC), manufacturers are expected to take into account the circumstances under which
their product is likely to be used. A manufacturer of firefighters' hoods should therefore be
expected to take into account the fact that they are likely to be worn with BA and a helmet
and attempt to accommodate any effects of this in their design.
To some extent during the fitting trials, but particularly during the wearer trials, firefighters
were asked about the effects (if any) which wearing a hood had on their movements. There
were reports with some styles that the hood restricted head movements, either from side to
37
side or looking down (for example to read a BA gauge). These problems were not common
to all styles of hood and appeared to be partly a function of hood style and partly the manner
in which the hood had been fitted by the wearer. Although clearly an important issue, the
results suggest that with careful styling, together with adequate instruction eg. in donning plus
training in the use of hoods, this problem can be avoided.
As part of the wearer trials, firefighters were questioned about their attitudes to fire hoods
before the trial was conducted. Some of those questioned had never worn a fire hood
previously (although this did not necessarily prevent them from having opinions). These
questions revealed that a significant minority thought that fire hoods interfered with the
wearer's ability to hear noises and isolated them from the environment. Despite this, most
thought that they were better protected when wearing one. After the wearer trials most
firefighters, perhaps not surprisingly, stated that they felt warmer when wearing the hood than
when uncovered. A minority thought that they had gone closer to the fire during the exercise
because they were wearing a hood. Most reported that wearing a hood had not adversely
affected their confidence during the exercise and that they would be willing to wear a hood
in the future. Interestingly, a considerable majority felt that the decision as to when to wear
a hood should be left to the individual.
Comments about isolation, particularly auditory isolation, are often made by firefighters when
the issue of fire hoods is raised with them. Although the number holding these views was
always in the minority it is nevertheless important to recognise that such views exist and, if
held by one particularly outspoken firefighter on a watch, this will have a significant influence
on the attitudes of others who have not experienced them and who hold no particular views
of their own.
The general pattern was for firefighters to acknowledge the improved protection offered by
fire hoods although some did express concerns that the increased isolation decreased their
sense of contact with the environment.
These findings confirmed the need for the subsequent series of controlled tests relating to
behaviour; heat transfer; sound attenuation and location; and physiological load.
The results relate to those hoods which are now known as fire hoods. Fitting trials (but not
wearer trials) were also conducted with the anti-flash hood manufactured to the E9
specification. The anti-flash hood is fitted round the brim of the firefighters' helmet. Many
modern designs of helmet incorporate a visor which causes a conflict with fitting an anti-flash
hood as the visor and its fastenings occupy the space on the front half of the helmet where
the anti-flash hood should be fitted. Some firefighters also experienced a conflict between
the anti-flash hood and their BA mask (with which the anti-flash hood has to be worn). Once
fitted, six out often firefighters complained that the transparent panel on the anti-flash hood
restricted their vision as it covered a smaller area than they wished.
These and the other criticisms documented in the results section (3.3) show that the E9
specification anti-flash hood interferes with the ability of the firefighters to perform their job;
and is incompatible with other forms of PPE thereby not complying with the PPE at Work
Regulations. However, this latter criticism is not entirely the fault of the E9 design as it is,
of course, compatible with the older pattern helmets, without a visor, once almost universally
issued within the fire service for which it was originally designed. As the anti-flash hood
serves a different purpose to the balaclava-style fire hoods it is clearly important that these
incompatibilities are resolved.
38
4.3 Behavioural Trials
It is a widely expressed concern that, with the additional protection provided by a fire hood,
firefighters might either inadvertently or deliberately expose themselves to a greater degree
of risk by modifying their behaviour in a call-out. It was agreed that the increased protection
would result in an increased isolation or reduced awareness of their environment lending to
greater risk-taking. These trials were established to examine these concerns.
Although the participants were not aware of this specific purpose of the study in which they
were involved they were nevertheless aware that they were under a degree of scrutiny and
this should be borne in mind in interpreting the result of these trials. Nevertheless, there was
no indication that wearing a fire hood had any influence on the performance of firefighters
either assessed objectively through their task performance times or through the independent
observation of their behaviour in selected key elements of the task. Helmet skirts did appear
to have some effect on performance time although the pattern of response was not always
consistent. By far the biggest influence on performance time and on behaviour during the
exercise was which brigade the firefighter was drawn from. Clear differences were
identifiable between brigades during the observations of the individuals and these differences
were reflected in the significant effect attributable to brigades from the statistical analysis.
It should be acknowledged that, as the safety observers were from the local brigade, they
would be most likely to expect the pattern of activity displayed by their local firefighters and
one element, that of producing a sketch map, was apparently unique to their training.
Nevertheless, the presence of an IOM observer was intended to minimise the influence of this
factor and the differences were not always attributable to this one brigade.
Although not shown by the formal analyses, there were some indications that those
firefighters who had seldom or never worn fire hoods before were more likely to display
adverse performance characteristics suggesting a period of uncertainty which should be
addressed by training. This was revealed in informal comments to the IOM researcher
present of feelings of slight apprehension in undergoing the novel experience (for them) of
wearing fire hoods.
Isolation from and consequent lack of awareness of the environmental temperature is often
regarded as an additional criticism of fire hoods. The results from this study, particularly
those from the hottest zone, zone 2, indicate that overall, firefighters are not very good at
estimating temperatures and that wearing a fire hood or helmet skirt does not have a
significant effect on this ability although the estimates of those wearing helmet skirts tended
to rise faster, presumably reflecting the tendency of these devices to funnel heat under the
helmet as shown in the physical tests (section 3.6.3) and discussed below (4.4). It is however
interesting to note that, in the third site for which estimates were obtained (zone 4) the
estimates remained elevated, even though the environmental temperature had fallen by this
time. This characteristic extended to the control group who were wearing a standard helmet
with no skirt or fire hood.
Finally, the subjective responses to wearing the fire hood or helmet skirts reflect many of the
same views as those documented elsewhere in the report, with a significant minority repeating
the views of increased isolation and lack of awareness frequently raised as barriers to the
wider introduction of fire hoods.
39
4.4 Physical Tests
The radiant heat transfer test performed on the fire hood fabrics was based upon the test
called up by the A26 specification used previously for garment fabric testing (Graveling et
al. 1996). The test is essentially similar to that specified in EN366. Althugh the radiant heat
flux is greater than the previous BSI test, the temperature rise accommodated is less. It is
interesting to note that these fabrics, although considerably less substantial than the multilayer
fabrics used for firefighters' tunics, nevertheless meet the A26 criteria of a minimum time of
30 seconds for an increase in temperature immediately behind the fabric of 25°C. The E9
anti-flash hood fabric of course provides even greater protection because its design results in
a considerable air gap between the fabric and the skin.
Clearly, if fire hoods are to be issued as standard equipment for firefighters then there has
to be some method of ensuring that such hoods provide a consistent minimum standard of
protection. Equally, because of the potential subjective discomfort involved (see below), it
is important that such hoods do not over-protect. The importance of subjective acceptance
should not be overlooked. Unlike many industrial contexts there is not normally any question
that firefighters will wear PPE when instructed to do so. However, over protection is
acknowledged to increase discomfort and dissatisfaction and the aim should be to provide the
level of protection required.
The measure of closeness of fit was primarily obtained as part of the radiant heat transfer
testing, to ensure that the hood fabric when tested was in a similar degree of stretch to when
worn on a head. However, several useful points can be made from these data. Firstly,
although not studied in these tests, the degree of stretch obtained from some hoods was
considerable (sometimes 40% or more) and would almost certainly have had a considerable
impact on heat transfer by reducing the thickness of the fabric. It is clearly important
therefore that some such control is included in any test of the thermal transfer qualities of
hood fabrics.
Secondly, tightness of fit has clear implications for physical comfort and acceptability.
Although no criteria are currently available on which an evaluative framework could be
based, it may be possible to design such a test based on correlational analyses between
objective measures of tightness such as that used here and subjective acceptability to a
representative sample of firefighters.
Concerns have been expressed about the build-up of heat inside a helmet when wearing (a)
a fire hood and, (b) the fabric skirts increasingly being provided by helmet manufacturers
during the life of the project. The results from oven tests, in which a standard sized model
head was subjected to elevated temperatures for 3.25 or 10 minutes (these figures are derived
from the NFPA standard for helmets) show that a helmet alone considerably reduces the
build-up of temperature on the head and that a further reduction is obtained through the use
of a fire hood. However, the tests using a helmet incorporating a skirt appear to confirm
reports from brigades that these skirts channel heat up into the head space. Although this
effect can be reduced by wearing a fire hood with the skirt, the temperatures achieved are still
greater than with a fire hood alone.
The skirt is of course intended to provide additional protection, supplementing the protection
by the rear brim of the helmet. Although the fire hood prevents immediate contact with hot
or burning debris the collar/hood area does potentially present an entrapment point for such
debris. However, it will result in an increase in direct heating of the head which may have
40
an adverse effect on health. Their continued or increased use should therefore be given
serious consideration, possibly with some investigation of the potential physiological/medical
effects of head heating of this magnitude.
Finally, a note of caution should be sounded. This study has shown how the use of a hood
can slow the rate of head heating compared to a helmet alone. The study did not however
examine the implications for head cooling. Experience has shown that measures taken to slow
the rate of increase in temperature will also decrease the rate of release of such heat as does
succeed in penetrating the barrier once the source of heat has been removed. This can have
a marked impact on subjective comfort as it prolongs the period for which wearers experience
thermal discomfort.
4.5 Audiometric/Sound Location Tests
The results from the wearer trials showed that a sizeable minority (36%) of the firefighters
questioned considered fire hoods to interfere with sounds. The results from the audiometric
tests clearly show that this is not the case, although the apparent resonance around 2kHz with
a helmet and skirt identified during the tests (see Table 3.23) could cause an increase in
background noise levels. This is of some concern because l-2kHz is a significant area of the
band of speech frequencies and could indicate a risk of masking at these critical frequencies.
Other than this, the mean differences at the different octave bands are of negligible practical
difference. It is interesting to note that the Gallet helmet also appears to create a degree of
resonance.
The results also demonstrate that the fire hoods, although covering the external ear (pinna)
do not have any notable impact on sound location (direction finding). Although some
firefighters did make mistakes there was nothing to suggest that this was consistently related
to wearing a fire hood. In the experience of some of the authors, more of a problem is likely
to result from multiple reflections of some loud, limited frequency signals used for DSUs.
However, these findings are clearly of great importance, given the comments above about the
beliefs of firefighters. It should be made quite clear to all firefighters that fire hoods do not
interfere with hearing and that they should not therefore be reluctant to wear fire hoods on
the basis of a misguided belief.
Although only a small sample, the results from the complete Gallet system do give some
cause for concern. The Gallet helmet system provides much more enclosing protection with
more of a solid barrier to sound waves. Although the attenuation figures are no different
from fire hoods or conventional helmets (apart from the resonance which they share with the
conventional helmet) the full system does appear to create some difficulties in sound location,
at least with DSU noise. It is possible that this effect is frequency dependant, the physical
cover being more of a barrier to high frequencies. This phenomenon should perhaps
therefore be investigated in more detail with a variety of signal frequencies.
4.6 Physiological Load
According to the firefighters who participated in the wearer trials of a variety of fire hoods,
such hoods make them feel hotter. However, this would appear to be purely a subjective
phenomenon as the physiological trials showed that the essential parameters of heart rate and
core temperature were not significantly affected. That is, when compared to wearing standard
41
A26 tunic and matching overtrousers, together with a standard issue helmet, the addition of
a fire hood does not significantly affect thermal balance. Nor is there any consistent effect
on the skin temperature of various regions of the head.
In the conditions of the tests, particularly with the high level of insulation on the rest of the
body, skin temperature is probably largely being determined by core temperature. As there
was little scope for heat loss, there was little opportunity to establish a thermal gradient
between the skin and the environment permitting significant heat loss.
The subjective findings do show changes in the expected direction (feeling hotter when
wearing a hood) although the mean changes are not large and were not statistically significant.
With a test of this nature it is impossible to avoid the possibility that subjective ratings are
based on expectation rather than actual experience.
A fire hood will provide some additional insulation and it is inevitable therefore that
firefighters will feel hotter as a result, particularly at lower environmental temperatures when
there is otherwise more opportunity for heat loss. At moderate temperatures, approximating
to body temperature, there is little opportunity for heat exchange and the impact of any such
covering is minimised. However, subjectively, freely dripping sweat may feel less
uncomfortable than that sweat being trapped next to the skin. Morris and Graveling (1986)
examined the concept of skin wettedness as a different subjective parameter to thermal
comfort or heat sensation and there appears to be some scientific validity for such an
approach.
At higher temperatures, the gradient is of course reversed, and it is interesting to note in this
context the results of the temperature estimations from the observational trials where, in the
hottest environments, those wearing the fire hood gave the lowest mean estimates of
environmental temperature (although this was not statistically significant). As with noise
attenuation/signal location it is important that this finding is communicated to firefighters.
4.7 General Discussion
This project examined fire hoods, their design and use, together with a number of the issues
which influence attitudes to their widespread introduction.
There can be little doubt, from the incidence of burn injuries to the otherwise exposed parts
of the face and neck, that wearing a fire hood should be seriously considered as standard
practice in any live fire situation. There have been a number of concerns and doubts
regarding this because of the alleged isolation effects of wearing a fire hood. This project
has shown these concerns to be unfounded. Wearing a hood did not cause firefighters to
behave any differently in a search and rescue scenario. It was anticipated that they might tend
to place themselves more at risk, either by not being as cautious in conducting safety checks
(eg before entering a room) or in remaining in the proximity of a fire for longer than they
would otherwise regard as prudent. This was not found to be the case. Differences in
behaviour were much more likely to result from differences between brigades, presumably
as a result of variations in training. Although this was not an element of the present study,
there are indications that training procedures should be examined and a degree of
standardisation considered.
42
Fire hoods are also regarded as increasing the sense of isolation, particularly thermal and
auditory, experienced by wearers and to increase the physiological strain experienced. Again,
tests conducted during this project have shown these to be unfounded. Covering a
firefighter's ears does not have a significant effect on that firefighters' ability to detect the
direction from which a noise is coming from nor does it cause any meaningful attenuation of
the intensity of the sound signal. They can make firefighters feel hotter, but not apparently
at higher temperatures and they have no significant effect on the ability of firefighters to
estimate the environmental temperature. They will however slow the rate of heat transfer and
will therefore provide a firefighter with additional protection.
Most of the fire hoods examined during the course of this project were acceptable for use by
firefighters. The two serious shortcomings, which would render a fire hood unsuitable for
use within the fire service, were where the facial opening was not adequate to accommodate
a BA face mask and where the fire hood did not have an extended yoke. Tests showed that
such fire hoods could ride up during wear, allowing a gap to form between the hood and the
collar of the fire tunic. Since the completion of the study, informal reports have been
received of burn injuries being sustained from hot debris falling into the gap between a tunic
collar and the neck. A well-designed fire hood would probably have reduced if not removed
the risk of injury in such circumstances.
Apart from these factors there were other minor shortcomings to the design of some fire
hoods currently commercially available. A good fire hood should be designed to be
compatible with the design of other forms of PPE with which it is likely to be worn. Thus
it should be reasonably close fitting without loose or bulky fabric which impairs the stability
or comfort of the helmet. However, it should not be so tight as to be difficult to put on over
BA face mask straps. The whole hood should be of a size and shape appropriate for the
individual and to ensure an adequate overlap between BA face mask and hood and between
hood and tunic to maintain the integrity of the cover during typical activities involving head
and neck movements.
The fabric used in their manufacture should be adequately flexible and yielding to maintain
this overlap without unduly restricting movement and without recourse to bulky excesses of
material which might in themselves create a hazard. Although current fabrics all appear to
be adequate, care should be taken to avoid over-protection as this will increase thermal
discomfort, particularly at lower temperatures. Consideration should be given to establishing
a maximum level of protection as well as a minimum in this context.
Attention to these design principles should ensure that the manufacturers and providers of fire
hoods comply with the appropriate aspects of the EC-derived Regulations relevant to them.
Clearly therefore, there is some scope for improvement in existing designs of fire hood. The
most important requirement however is for the widespread promulgation of the findings of
this research to counter the attitudes of a minority of firefighters who harbour concerns about
these valuable protective devices. Firefighters should be informed that a fire hood will not
make it harder for them to hear, nor will wearing one significantly affect their ability to
determine the temperature of their surroundings. They should also be informed that a fire
hood will make them warm when it is cooler (although this can be beneficial during the
winter months) but that this is not reflected in a significant increase in physiological load
when it really matters and that the discomfort is worth tolerating against the risk of
disfiguring burns.
43
5. CONCLUSIONS
1.
The main areas of firefighters' bodies sustaining burn injuries are those areas of the
head and neck not otherwise covered by their helmet; BA face mask; and tunic collar.
This would appear to provide a strong justification for the widespread introduction
of fire hoods within the fire service.
2.
Wearing a fire hood does not significantly impair task performance by encouraging
firefighters to remain longer in a potentially dangerous environment or by
encouraging them to adopt other unsafe behavioural practices.
3.
Fire hoods do not significantly impair the ability of firefighters to estimate the
temperature of their surroundings - firefighters are not very good at estimating
temperatures regardless of the type of head gear worn.
4.
Fire hoods do not however significantly increase physiological strain either by
increasing the load on the heart or by elevating body temperature.
5.
Fire hoods provide an additional level of thermal protection complying with the
minimum standard of radiant heat transfer specified under the A26 (tunic)
requirements.
6.
In common with other insulative clothing, fire hoods will (a) result in some
discomfort, particularly in 'temperate' climates and (b) retain heat after a period of
exposure possibly adding to observations of thermal discomfort.
7.
A significant minority of firefighters harbour the belief that fire hoods have adverse
effects such as impaired hearing or increased isolation to the point of endangering the
wearer.
8.
Most fire hoods currently commercially available can be worn safely and effectively
by firefighters. The exceptions are those where the face opening is insufficiently
large to accommodate the BA face mask and those without a neck yoke which do not
provide adequate overlap with the firefighters' tunic.
9.
Most will cause minor problems for some firefighters, depending upon head shape
and size, although not sufficient to endanger the safety of the wearer. These
problems may be surmountable by offering individuals a choice of styles.
Alternatively, manufacturers may modify designs or offer a variety (eg of sizes)
within a style.
10.
In selecting/ designing a fire hood, the following factors should be taken into account:
i)
The whole hood should be of a size and shape to ensure an adequate overlap
between hood and tunic and between BA face mask and hood to avoid areas
of skin becoming exposed during wearings;
ii)
The whole hood should be reasonably close fitting without loose or bulky
fabric which may impair the stability or comfort of the helmet;
iii)
the whole hood should not be so tight as to be difficult to put on over BA
iv)
face mask straps without inadvertently loosening them;
The fabric used in their manufacture should be sufficiently flexible and
yielding so as to avoid unduly restricting movements;
44
v)
The fabric used in their manufacture should provide reasonable heat
protection (those tested in the present study appear adequate) but should avoid
over-protection which may increase thermal discomfort.
11.
Helmet skirts do channel heat up into the head space so their continued/increased use
should be given careful consideration.
12.
Wearing the Gallet helmet did result in firefighters making mistakes in sound
location, at least with DSU noise - this phenomenon requires further investigation
with a variety of signal frequencies.
45
6.
RECOMMENDATIONS
1.
Serious consideration should be given to the issue of fire hoods to all firefighters as
part of standard fire kit.
2.
An awareness campaign needs to be developed amongst firefighters to promulgate the
findings of this research and to promote the widespread acceptance, distribution and
use of fire hoods.
3.
Training should be given to firefighters in the use of fire hoods. This should include:
i)
donning - fitting over BA mask straps; checks for fit around mask; etc.
ii)
use - experiencing their use in live fires
iii)
doffing - worn over the BA face mask it should naturally be removed with
the face mask after an incident to reduce thermal discomfort.
4.
Consideration should be given to devising a standard specification for fire hoods for
use in the fire service including maximum as well as minimum insulation levels and
compatability with BA face masks and helmets.
5.
Fire hood manufacturers should be encouraged to modify and improve the designs of
their products in the light of the detailed findings described in this report.
46
47
ACKNOWLEDGMENTS
We thank the following people and organisations for their assistance and co-operation during
the course of this study.
The Home Office, for funding the study as part of their ongoing fire research programme.
The officers and staff at the International Fire Training School, Chorley, Lancashire, the
officers and staff of the Scottish Fire Training School, Gullane and the Royal Berkshire Fire
and Rescue Service Training School for the provision of facilities and support during the
various trials.
All the brigade liaison officers who helped to distribute and complete questionnaires; all the
firefighters who participated so willingly in the various exercises.
Officers and firefighters from other brigades who assisted in the development of
questionnaires and at other points during the research.
Ms S Coles, Project Officer, Home Office, Fire Research and Development Group for her
unstinting help, encouragement and assistance at all times during this research.
Mr R Howie, formerly of the IOM, for his assistance in devising and assembling the fabric
tests.
Finally, Mrs M Brebner and typing staff at the Home Office for typing the manuscript and
other members of IOM staff who contributed to the work at some point.
48
49
REFERENCES
BS3791:1970 (withdrawn). Specification for clothing for protection against intense heat for
short periods. London: British Standards Institute.
BSEN366:1993. Protective clothing. Protection against heat and fire. Method of test:
evaluation of materials and material assemblies when exposed to a source of radiant heat.
London: British Standards Institute.
CEC (1989). Council Directive of 21 December 1989 on the approximation of the laws of
the Member States relating to personal protective equipment. (89/686/EEC). Official Journal
of the European Communities; 18(L399): 18-38.
Genstat 5 Committee. (1987). Genstat 5 reference manual. Oxford: Clarendon Press.
Graveling RA, Johnstone JBG, Butler DM, Crawford J, Love RG, Maclaren WM, Ritchie
P (1996). Study of the degree of protection afforded by firefighters' clothing. Edinburgh:
Institute of Occupational Medicine (IOM Report TM/96/02).
HSE (1992). Personal Protective Equipment at Work Regulations 1992. London: HMSO.
Love RG, Johnstone JBG, Crawford J, Tesh KM, Graveling RA, Ritchie P, Hutchison PA,
Wetherill GZ (1994). Study of the physiological effects of wearing breathing apparatus.
Edinburgh: Institute of Occupational Medicine OOM Report TM/94/05).
Morris LA, Graveling RA (1986). Response to intermittent work in hot environments.
Edinburgh: Institute of Occupational Medicine (IOM Report TM/86/07).
National Fire Protection Association (1987). NFPA:1972, Standard on helmets for structural
firefighting. Quincy:MA, NFPA.
Stevenson CJ (1985). Effects of radiant heat in firefighting instructors. British Journal of
Industrial Medicine; 42:67-68.
50
51
Table 3.1 Fire hoods and anti-Hash hoods used
HOOD
MANUFACTURER
DESCRIPTION
Cairns and Brother
A loose fitting balaclava with a
yoke made of a single layer of
a heavy Nomex (white)
Cairns and Brother
A balaclava of the same design
as A but made of a lighter
weight PBI/Rayon fabric (beige)
Diktron Developments11
A balaclava style with a yoke and
sewn in perforated ear pieces,
made from a single layer of
Nomex III (cream)
Martinsons 'Protekta'
A balaclava style with a yoke and
sewn in perforated ear pieces,
made from a Proban treated cotton
flannelette (blue)
Public Uniform
Company (PUC)
A balaclava style with a yoke
made from a double layer of
Kennel/Viscose with earholes in
the inner layer (blue)
Rhone-Poulenc
A balaclava style with a long yoke made
from a single layer of Kermel/Viscose
(blue)
Heathcote Fabrics
A replacement for F. A balaclava style
with a shorter yoke made from a double
layer of Kermel/Viscose (blue)
H
Tempo Uno
A balaclava style made from Nomex III
(outer) and wool (lining)
I
Tempo Uno L
Similar to h but with no lining layer
J
Warm 'n Dry
A balaclava style with no yoke made
from a single layer Kermel/Viscose
fabric with a fleecy inner surface
(blue)
K
Warm 'n Dry
A balaclava of the same design as J but
made from a Wool/Kermel Zirpo treated
fabric (blue)
Bristol Uniforms
E9 specification anti-flash hood (yellow)
B
D
*later versions did not have ear pieces
52
Table 3.2
Attitudes of firefighters participating in wearer trials to the use of fire
hoods - numbers agreeing with statements.
Qi
Q2
Q3
Q4
A
10
4
3
4
B
6
7
6
3
C
4
7
4
6
D
7
8
3
4
E
3
10
7
8
G
11
2
4
0
K
8
8
4
5
HOOD
N.B. All based on a sample size of 12.
Key
Question 1.
A fire hood provides essential additional protection.
Question 2.
A fire hood produces a loss of sensory content.
Question 3.
A fire hood produces adverse heat isolation.
Question 4.
A fire hood adversely affects hearing ability.
53
Table 3.3
Distribution of firefighters participating in the observational trials by
brigade and fire hood group
FIRE HOOD GROUP
Control
Skirt
Hood
Hood & Skirt
Total
4
3
1
2
10
5
0
7
4
16
1
2
0
0
3
South Glamorgan
0
5
0
0
5
5 Hampshire
4
4
6
7
21
TOTAL
14
14
14
13
55
Brigade
1
Oxfordshire
2
Berkshire
3
Buckinghamshire
4
54
Table 3.4
Mean time (minutes) in zones 1-4, subdivided according to fire hood group.
Condition
Location
Skirt
Control
Mean
Time
No of
Subs
Mean
Time
Fire hood
No of
Subs
Mean
Time
No of
Subs
TOTAL
Fire hood & Skirt
Mean
Time
No of
Subs
Mean
Time
No of
Subs
Zone 1
3.44
14
4.07
14
3.55
14
3.41
13
3.52
55
Zone 2
1.52
14
2.05
14
1.49
14
1.31
13
1.83
55
Zone 3
5.21
14
4.02
14
4.38
14
4.55
13
4.73
55
Zone 4
1.50
14
1.55
13
1.43
14
1.55
13
1.51
54
55
Table 3.5
Results of the regression analysis of time in zone 2 (modelled on the log
scale). Tabulated values are estimated regression coefficients; the ratio of
estimate to standard error is in parenthesis. Ratio values of two or more
indicate statistical significance at the 5% level.
Model 1
Model 2
Model 3
Model 4
Model 5
Actual Temperature
-0.0008
(-0.33)
-0.0021
(-0.85)
-0.0015
(-0.58)
-0.0036
(-0.99)
-0.0045
(-1.23)
Hood group : Hood
0.143
0.01)
0.118
(0.72)
1.148
(1.31)
1.548
(1.76)
Skirt
-0.031
(-0.23)
0.024
(0.17)
-0.447
(-0.71)
-0.615
(-0.99)
Hood & Skirt
-0.177
(-1.26)
-0.137
(-0.95)
-1.594
(-2.29)
-1.174
(-1.66)
Brigade:
2
-0.311
(-2.22)
-0.276
(-1.81)
-0.348
(-2.29)
3
-0.399
(-1.72)
-0.477
(-1.98)
-0.292
(-1.22)
4
-0.007
(-0.03)
-0.116
(-0.53)
-0.018
(-0.08)
5
-0.364
(-2.59)
-0.321
(-2.14)
-0.372
(-2.38)
Temp. Hood group: Hood
-0.0083
(-1.10)
-0.0126
(-1.64)
Skirt
0.0039
(0.68)
0.0062
(1.09)
Hood & Skirt
0.0125
(2.06)
0.0094
(1.54)
Intercept Constant
0.644
(2.3.9)
1.027
(3.28)
0.945
(2.96)
0.945
(2.37)
1.296
(3.05)
Residual ss
df
6.402
49
5.813
48
5.496
45
5.510
46
4.636
42
56
Table 3.6
Model 1
Model 2
Model 3
Model 4
Model 5
Actual Temperature
0.0063
(0.43)
0.0065
(0.41)
0.0026
(0.18)
0.0044
(0.19)
0.0081
(0.34)
Hood group : Hood
-0.569
(-2.87)
-0.798
(-3.46)
-3.53
(-1.71)
-1.76
(-0.72)
Skirt
-0.209
(-1.07)
-0.147
(-0.77)
-0.20
(-0.12)
0.25
(0.14)
Hood & Skirt
-0.148
(-0.74)
-0.059
(-0.30)
1.37
(0.78)
0.95
(0.53)
Brigade:
2
0.142
(0.65)
-0.052
(-0.24)
-0.051
(-0.23)
3
-0.121
(-0.34)
0.129
(0.39)
0.155
(0.44)
4
-0.074
(-0.25)
0.471
(1.52)
0.349
(0.87)
5
-0.266
(-1.28)
-0.350
(-1.78)
-0.326
(-1.58)
Temp. Hood groupHood
0.0627
(1.44)
0.0213
(0.40)
Skirt
-0.0001
(0.00)
-0.0085
(-0.22)
Hood & Skirt
-0.0334
(-0.88)
-0.0222
(-0.57)
Intercept Constant
1.332
(1.90)
1.165
(1.52)
1.615
(2.22)
1.420
(1.29)
1.350
(1.16)
Residual ss
df
12.952
49
13.734
48
10.644
45
11.890
46
10.476
42
57
Table 3.7
Model 1
Model 2
Model 3
Model 4
Model 5
Actual Temperature
-0.0013
(-0.09)
-0.0115
(-0.85)
-0.0149
(-1.06)
0.0105
(0.40)
0.0047
(0.20)
Hood group : Hood
0.015
(0.10)
0.048
(0-47)
1.01
(0.72)
1.78
(1.27)
Skirt
-0.167
(-1.14)
-0.260
(-1.87)
0.75
(0.51)
0.66
(0.49)
Hood & Skirt
0.045
(0.30)
-0.036
(-0.26)
-0.64
(-0.35)
0.23
(0.13)
Brigade:
2
0.205
0.41)
0.307
(1.99)
0.323
(2.02)
3
0.222
(0.93)
0.167
(0.69)
0.075
(0.29)
4
0.415
(2.08)
0.356
(1.60)
0.317
(1.39)
5
0.446
(3.12)
0.519
(3.50)
0.532
(3.49)
Temp. Hood groupHood
-0.0260
(-0.71)
-0.0443
(-1.24)
Skirt
-0.0247
(-0.63)
-0.0253
(-0.70)
Hood & Skirt
0.0173
(0.37)
-0.0081
(-0.17)
Intercept Constant
0.630
(1.19)
0.710
(1.38)
0.857
(1.64)
0.199
(0.21)
0.137
(0.16)
Residual ss
df
7.285
49
6.250
48
5.662
45
7.094
46
5.442
42
58
Table 3.8
Results from a REML model of time in zones 1, 2, 3 and 4
Variable
Wald statistic df
Brigade
2.3
4
Fire Hood Group
2.2
3
247.3
3
Brigade : Fire Hood Group
8.1
6
Brigade : Zone
24.4
12
Fire Hood Group : Zone
13.8
9
Zone
***
p<0.001
*
p<0.05
Table 3.9
Zone 2
Zone 4
*
Perceived and actual environmental temperatures (mean values, °C)
Mean Temperature
Zone 1
***
Perceived
Actual
Control
35.8
35.9
Skirt
37.0
38.1
Hood
29.2
33.1
Hood & Skirt
31.5
36.9
Control
54.6
106.4
Skirt
65.8
116.6
Hood
37.7
111.4
Hood & Skirt
53.2
115.5
Control
56.2
36.6
Skirt
64.4
39.7
Hood
39.6
37.5
Hood & Skirt
47.5
38.2
59
Table 3.10
Results of the regression analysis of perceived temperature in zone 1
(modelled on the log scale). Tabulated values are estimated regression
coefficients; the ratio of estimate to standard error is in parenthesis. Ratio
values of two or more indicate statistical significance at the 5% level.
Model 1
Model 2
Model 3
Model 4
Model 5
Actual Temperature
0.410
(1.25)
0.118
(0.35)
-0.014
(-0.04)
-0.330
(-0.52)
-0.642
(-1.04)
Hood group : Hood
0.054
(0.38)
-0.039
(-0.25)
-7.75
(-2.53)
-10.20
(-2.89)
Skirt
-0.124
(-0.92)
-0.093
(-0.68)
-1.31
(-0.47)
-1.37
(-0.51)
Hood & Skirt
-0.085
(-0.61)
0.020
(0.15)
0.67
(0.14)
-0.56
(-0.12)
Brigade:
2
-0.174
(-1.25)
-0.146
(-0.94)
-0.110
(-0.76)
3
0.085
(0.40)
0.111
(0.48)
-0.196
(-0.83)
4
0.143
(0.55)
0.198
(0.67)
-0.505
(-1.41)
5
-0.327
(-2.50)
-0.325
(-2.31)
-0.322
(-2.46)
Temp. Hood group :
Hood
2.177
(2.55)
2.890
(2.89)
Skirt
0.318
(0.40)
0.339
(0.45)
Hood & Skirt
-0.210
(-0.16)
0.160
(0.12)
Intercept Constant
2.04
(1.73)
3.21
(2.68)
3.70
(2.72)
4.69
(2.06)
5.95
(2.68)
Residual ss
df
4.363
40
3.657
39
3.584
36
3.502
37
2.792
33
60
Table 3.11
Model 1
Model 2
Model 3
Model 4
Model 5
Actual Temperature
0.754
(2.28)
0.320
(0.98)
0.358
(1.06)
0.678
(1.42)
0.347
(0.76)
Hood group : Hood
0.071
(0.34)
0.040
(0.18)
-2.34
(-0.41)
3.46
(0.60)
Skirt
-0.438
(-2.23)
-0.257
(-1.34)
0.15
(0.04)
-1.80
(-0.49)
Hood & Skirt
-0.167
(-0.80)
-0.002
(-0.01)
-2.06
(-0.44)
2.30
(0.51)
Brigade:
2
-0.594
(-3.10)
-0.478
(-2.28)
-0.548
(-2.39)
3
-0.271
(-0.88)
-0.317
(-0.99)
-0.292
(-0.86)
4
-0.162
(-0.59)
-0.218
(-0.71)
-0.195
(-0.60)
5
-0.775
(-4.10)
-0.707
(-3.53)
-0.799
(-3.49)
Temp. Hood group :
Hood
Skirt
-0.123
(-0.15)
0.334
(0.42)
Hood & Skirt
0.400
(0.40)
-0.483
(-0.50)
Intercept Constant
Residual ss
df
0.510
(1.42)
-0.730
(-0.59)
0.42
(0.27)
2.80
(1.80)
2.63
(1.65)
0.77
(0.35)
2.73
(1.28)
11.550
45
9.419
8.831
41
11.440
42
8.638
44
38
61
Table 3.12
Model 1
Model 2
Model 3
Model 4
Model 5
Actual Temperature
0.021
(0.04)
0.618
(1.21)
0.573
(1.03)
0.887
(0.91)
0.993
(1.18)
Hood group : Hood
0.118
(0.64)
-0.032
(-0.17)
2.75
(0.46)
-6.24
(-1.03)
Skirt
-0.336
(-2.20)
-0.212
(-1.48)
5.90
(1.14)
5.81
(1.29)
Hood & Skirt
-0.148
(-0.87)
-0.024
(-0.15)
6.36
(0.79)
4.41
(0.60)
Brigade:
2
-0.394
(-2.52)
-0.322
(-1.91)
-0.348
(-2.06)
3
0.221
(0.92)
0.203
(0.80)
0.439
(1.50)
4
-0.133
(-0.47)
-0.134
(-0.44)
-0.079
(-0.26)
5
-0.541
(-3.61)
-0.498
(-3.16)
-0.509
(-3.28)
Temp. Hood group:
Hood
-0.740
(-0.46)
1.640
(1.00)
Skirt
-1.730
(-1.20)
-1.660
(-1.33)
Hood & Skirt
-1.790
(-0.81)
-1.210
(-0.60)
Intercept Constant
3.88
(1.83)
1.93
(1.04)
2.13
(1.06)
0.77
(0.22)
0.62
(0.20)
Residual ss
6.358
4.968
4.633
6.088
4.093
40
37
38
34
df
41
62
Table 3.13
Assessment of quality of Gauge Check procedures
Control
Total for
all brigades
Table 3.14
Table 3.15
Table 3.16
Total
7
2
2
16
Good
9
7
12
11
39
Total
14
14
14
13
55
Assessment of quality of Door Procedures
Skirt
Fire hood
Fire hood
& Skirt
Total
Poor
3
6
4
1
14
Good
11
8
10
12
41
Total
14
14
14
13
55
Assessment of quality of Stair Safety Procedures
Skirt
Fire hood
Fire hood
& Skirt
Total
Poor
3
1
4
5
13
Good
11
13
10
8
42
Total
14
14
14
13
55
Assessment of quality of Search Procedures
Control
Total for
all brigades
Fire hood
& Skirt
5
Control
Total for
all brigades
Fire hood
Poor
Control
Total for
all brigades
Skirt
Skirt
Fire hood
Firehood
& Skirt
Total
Poor
3
8
4
4
19
Good
11
6
10
9
36
Total
14
14
14
13
55
63
Table 3.17
Assessment of quality of Ground Floor Sketch
Control
Total for
all brigades
Table 3.18
Fire hood
Fire hood
& Skirt
Total
Poor
3
3
3
1
10
Good
11
11
11
12
45
Total
14
14
14
13
55
Assessment of quality of First Floor Sketch
Control
Total for
all brigades
Skirt
Skirt
Fire hood
Fire hood
& Skirt
Total
Poor
8
10
5
3
26
Good
6
4
9
10
29
Total
14
14
14
13
55
64
Table 3.19
Time (sees) for temperature increase of 25°C behind hood fabric.
Manufacturer
Mean
S.D
1
Cairns and Brother Inc
61.58
2.18
-
-
2
Cairns and Brother Inc
46.93
2.95
-
-
3
Diktron Developments Ltd
35.36
0.96
-
-
4
Heathcote Fabrics
42.77
2.32
slight
-
5
Mattinson Brothers Ltd
48.99
2.61
-
-
6
PUC
54.42
8.47
severe
yes
7
Rhone Poulenc
32.63
1.42
slight
8
Tempo Uno L
47.73
1.17
-
yes
-
9
Warm and Dry
34.89
2.90
slight
yes
10
Warm and Dry
35.83
2.62
slight
yes
Hood
no
Scorching
Fumes produced
65
Table 3.20
Hood
Stretch of fabric and looseness around neck of each hood on a standard
head.
Manufacturer
No
Stretched size
(mm) (from
100 mm)
Closeness of fit
Loose
fabric at
neck
(mm)
1
Cairns & Bro. Inc
125
loose over head and neck
75
2
Cairns & Bro. Inc
140
quite loose over head
40
3
Diktron Dev. Ltd
130
tight over head
30
4
Heathcote Fabrics
130
tight over head and neck
00
5
Mattinson Bros. Ltd
117
loose from below ears
50
6
PUC
140
tight over head and neck
00
7
Rhone Poulenc
147
quite loose below ears
30
8
Tempo Uno L
120
quite loose over head and
neck
35
9
Warm 'n Dry
125
quite loose below ears
15
10
Warm 'n Dry
120
tight over head
20
Table 3.21
Surface temperatures (°C) on head after heating 250°C for 3.25 minutes
Conditions
Head Temperature (°C)
Control
77
Gallet Helmet
30
Cromwell Helmet
30
Cromwell Helmet + Fire Hood
26
Cromwell Helmet + Fire Hood + Skirt
32
Cromwell Helmet + Skirt
38
66
Table 3.22
Surface temperatures (°C) on head after heating at 200°C for 10 minutes
Conditions
Control
Head Temperature (°C)
111
Gallet Helmet
45
Cromwell Helmet
48
Cromwell Helmet + Fire Hood
38
Cromwell Helmet + Fire Hood + Skirt
42
Cromwell Helmet + Skirt
52
67
Table 3.23
Sound attenuation (dB, means ± standard deviation) obtained for all helmets and hoods
Octave Band Frequency
Helmet and hood
Gallet
(no skirt)
63Hz
125Hz
250Hz
SOOHz
1kHz
2kHz
4kHz
8kHz
16kHz,
0.7 ± 2.4
0.7 ± 1.6
1.7 ± 0.8
0.7 ± 1.6
0.3 ± 2.7
5.7 ± 2.3
0.7 + 3.5
0.7 + 1.0
-0.7 ± 3.5
Gallet
( + lining and collar)
-0.3 ± 1.5
-1.3 ± 1.0
0.7 ± 1.0
-1.0 ± 1.1
-0.3 ± 2.0
3.3 ± 3.0
-1.7 ± 2.0
-1.0 ± 1.7
-3.7 ± 2.0
Helmet and short skirt
-0.2 ± 1.3
0.5 ± 0.9
0.5 ± 0.9
1.2 ± 1.8
2.7 ± 2.4
7.0 ± 4.1
-0.5 ±3.0
-1.0 ± 3.2
-1.2 ± 6.1
Helmet and long skirt
-0.2 ± 1.7
0.5 ± 1.4
0.7 ± 1.5
0.2 ± 1.3
1.2 ± 1.8
5.7 ± 2.7
0.7 ± 1.8
-0.7 ± 1.8
-2.0 ± 4.3
Warm 'n Dry
-1.0 ± 1.2
-1.0 ± 1.7
-0.7 ± 1.0
0.0 ± 1.6
1.7 ± 3.9
2.0 ± 2.2
1.3 ± 3.5
0.7 ± 1.0
1.0 ± 1.7
Cairns & Brother, PBI
-0.7 ± 1.0
0.3 ± 0.8
0.3 ± 0.8
0.7 ± 1.0
-0.3 ± 1.5
0.0 ± 1.3
-0.7 ± 1.0
-0.3 ± 0.8
-0.3 ± 1.5
Mattinsons
-0.8 ± 1.6
-0.6 ± 1.6
-1.6 ± 2.0
-0.2 ± 1.3
0.5 ± 3.7
0.7 ± 2.8
0.5 ± 3.7
-1.2 ± 1.8
0.0 ± 2.4
Cairns & Brother, Nomex
-0.9 ± 1.6
0.0 ± 1.6
0.4 ± 1.6
0.2 ± 1.5
-0.4 ± 1.8
-0.2 ± 2.9
0.0 ± 1.3
-0.4 ± 1.6
-0.6 ± 2.1
0.7 ± 1.2
0.3 ± 1.5
-1.0 ± 1.1
-0.3 ± 1.5
-4.3 ± 3.4
-3.0 ± 1.7
1.7 ± 1.5
-0.3 ± 0.8
-0.3 ± 2.3
-1.3 ± 1.2
0.0 ± 2.4
-1.3 ± 2.4
-0.3 ± 0.8
-0.7 ± 2.4
0.7 ± 4.6
0.7 ± 4.7
-0.7 ± 2.4
1.0 ± 3.5
1.5 ± 1.9
0.3 ± 1.5
0.0 ± 0.0
0.7 ± 2.4
-2.3 ± 2.0
-2.7 ± 2.1
1.7 ± 2.3
0.0 ± 3.3
1.3 ± 4.7
-2.0 ± 0.0
-0.3 ± 1.5
-0.7 ± 1.0
0.3 ± 2.3
2.0 ± 4.0
1.3 ± 2.1
2.0 ± 2.2
2.3 ± 2.0
3.3 ± 2.4
Diktron
Rhone-Poulenc
Practical Uniform Co
Heathcote
NB: Attenuation is indicated by negative values.
68
Table 3.24
Results of sound location tests on other protective headgear
Type of Headgear
Number of Tests
Frequency of errors
per test
0 1 2 3 4
Bristol Firebird helmet
with long neck curtain
4
3 - - 1 -
Bristol Firebird helmet
with short neck curtain
3
2 ...
Gallet Fl helmet
3
2 -
1 - -
Gallet Fl helmet with
lining and collar
4
1 2
1 - -
14
8 2 2 1 1
TOTAL
Table 3.25
1
Mean final heart rates (beats min"1), adjusted for initial heart rate and climate
environmental temperature.
A: Comparison between PUC and Cairns hoods
Hood Up
Hood Down
Total
PUC
137.3
137.5
137.4
Cairns
139.3
133.8
136.6
Total
138.3
135.7
137.0
B: Comparison between Cairns hood with no skirt, long skirt and short skirt
Hood Up
Hood Down
Total
No Skirt
139.3
133.8
136.6
Long Skirt
137.4
136.9
137.2
Short Skirt
140.5
136.5
138.5
Total
139.1
135.8
137.4
No Skirt
With Skirt
Total
139.7
139.4
139.6
C: Comparison between Gallet helmets
Gallet
69
Table 3.26
Mean final aural temperature (°C), adjusted for initial aural temperature and
environmental temperature.
A: Comparison hetween PUC and Cairns hoods
Hood Up
Hood Down
Total
PUC
37.15
37.09
37.12*
Cairns
37.29
37.31
37.30*
Total
37.22
37.20
37.21
* Significant p = .05
Hood Up
Hood Down
Total
No Skirt
37.29
37.31
37.30
Long Skirt
37.35
37.06
37.20
Short Skirt
37.30
37.15
37.22
Total
37.31*
37.17*
37.24
*Significant p = .05
C: Comparison hetween Pallet helmets
No Skirt
Gallet
37.26
With Skirt
37.22
Total
37.24
70
Table 3.27
Mean final temperature (°C) site 1 (forehead), adjusted for initial temperature
site 1 and environmental temperature.
Hood Up
Hood Down
Total
PUC
35.28
35.90
35.59
Cairns
35.07
35.80
35.44
Total
35.18**
35.85**
35.51
"Significant p = .01
B: Comparison between Cairns hood with no skirt, long skirt, short skirt
Hood Up
Hood Down
Total
No Skirt
35.07
35.80
35.44
Long Skirt
36.02
35.54
35.78
Short Skirt
35.50
35.91
35.71
Total
35.53
35.75
35.64
C: Comparison between Pallet helmets
Gallet
No Skirt
With Skirt
Total
35.37
35.57
35.47
71
Table 3.28
Mean final skin temperature (°C) site 2 (left cheekbone), adjusted for initial
temperature site 2 and environmental temperature.
Hood Up
Hood Down
Total
PUC
32.07
31.70
31.88
Cairns
32.02
32.06
32.04
Total
32.04
31.88
31.96
Hood Up
Hood Down
Total
No Skirt
32.02
32.06
32.04
Long Skirt
31.38
31.68
31.53
Short Skirt
31.43
31.78
31.60
Total
31.61
31.84
31.72
Gallet
No Skirt
With Skirt
Total
31.60
31.73
31.66
72
Table 3.29
Mean final skin temperature (°C) site 3 (lower left jawbone) adjusted for initial
Hood Up
Hood Down
Total
PUC
35.10
35.10
35.10
Cairns
35.08
35.40
35.24
Total
35.09
35.25
35.17
Hood Up
Hood Down
Total
No Skirt
35.08
35.40
35.24
Long Skirt
35.40
35.34
35.37
Short Skirt
35.54
34.93
35.24
Total
35.34
35.22
35.28
No Skirt
Gallet
*Significant p = .05
34.73*
With Skirt
35.68*
Total
35.20
73
Table 3.30
Mean final skin temperature (°C) site 4 (back of neck) adjusted for initial
Hood Up
Hood Down
Total
PUC
35.74
35.86
35.80**
Cairns
35.01
35.18
35.10**
Total
35.37
35.52
35.44
**Significant p = .01
Hood Up
Hood Down
Total
No Skirt
35.01
35.18
35.10*
Long Skirt
35.60
35.34
35.47*
Short Skirt
35.57
35.70
35.63*
Total
35.39
35.41
35.40
*Differences between the no skirt condition and the combined skirt conditions, significant p = .05
Gallet
**c;Significant
p = .01
No Skirt
With Skirt
Total
34.74**
36.06**
35.40
74
Table 3.31
No.
Mean ratings of perceived body temperature.
Name
Perceived
whole body
temperature
Perceived
head
temperature
1
PUC
3.1
3.5
2
PUC control
3.1
3.0
3
Cairns
3.3
3.3
4
Cairns control
3.1
2.9
5
Long Skirt
3.4
3.6
6
Long Skirt
control
3.1
3.4
7
Short Skirt
3.3
3.8
8
Short Skirt
control
3.1
3.0
9
Gallet
3.0
3.7
10
Gallet with
Skirt
3.4
3.9
GROUND FLOOR SHOP
COLLAPSED STRUCTURE /RAT RUN
ui
\
STAIRS
BURN ROOM
End of Zone 1
Timing A start
of Zone 2 timing
Start of Zone I
timing A end of
Zone 5 timing.
ENTRANCE
Figure 2.1:
Observational trials: ground floor route
End of 2*0-4
tuning & startof
Zone 5 timing
CORRIDOR
EndofZone^
\
timing and start
of Zone 4 timing
KITCHEN
BEDROOM
LOUNGE
LANDING
End of Zone 2
timing & start of
Zone 3 tufan
STAIRS'
Figure 2.2:
Observational trials: first floor route
APPENDIX A
Brigade Questionnaire
The Protection Afforded by Firefighters' Protective Clothing
Brigade Questionnaire
Instructions
This questionnaire is part of a 3 year study commissioned by the Home Office on the degree of protection
afforded by firefighters' protective clothing. We hope that it will provide information on the clothing used in
the Fire Service. The study will investigate the protection afforded by and any additional thermal load caused
by the A26 and similar specification clothing. The work will also include assessments of alternative outer
garments eg. one piece ensembles and clothing based upon the 'layered' approach.
The general aim
is to investigate the clothing in terms of its thermal protective performance, comfort, suitability and its
capacity to induce excessive thermal loads on the wearers.
The questionnaire is divided into eleven sections r a n g i n g from the introduction of the A26 specification
tunics to the rank markings.
There are three types of question; an example of each is shown below.
1. Factual information such as manufacturer(s) and style(s) of clothing should be entered in the relevant
space.
eg. Al. Please specify the manufacturer(s) and style(s) of the fire tunics currently on issue in the
brigade.
Style
Manufacturer
Tunic 1
Bristol
Nornex Delta T
Tunic 2
PM.C.
Bunker Tunic
Tunic 3
2. In some questions you are asked to select your answer from a list of possible alternatives.
the appropriate answer and put the code number, letter or tick in the box provided.
eg. A2.
Does the t u n i c comply w i t h the A26 specification ?
Y = Yes
N = No
eg. A2.1 If NO, do you plan to buy A26 tunics within the next 1 = Year
2 = 2 Years
3 = 3 Years
4 = More than 3 Years
5 = Not planned
3. You may be asked to add f u r t h e r information in response to a particular question.
(Please answer in the box provided).
Please select
4. In addition you may be asked to enclose f u r t h e r written material. To help identify where this is
necessary, at the start of the questionnaire there is a checklist to be completed.
If you have any queries regarding the questionnaire or the questions asked, please contact Miss Julia
Johnstone or Ms Joanne Crawford at the Institute of Occupational Medicine, in Edinburgh, on (031) 667 5131
extension 2514.
When completed please return this questionnaire and any other documents requested, in the prepaid envelope
to the Institute of Occupational Medicine, 8 Roxburgh Place, Edinburgh EH8 9SU by 31st October, 92.
Please return this questionnaire even if the return date stated has passed.
Thank you for your co-operation.
This form was completed by :
dd
mm
yr
Date :
Telephone No:
When you have completed the questionnaire and are about to return it, can you please tick the appropriate
boxes on the checklist below, to ensure that you have enclosed the information requested.
If some of the
list is not a p p l i c a b l e to you, please put NA in the r e l e v a n t section.
1. S p e c i f i c a t i o n for t u n i c s
2. S p e c i f i c a t i o n for o v e r t r o u s e r s
3. Q u e s t i o n n a i r e for e v a l u a t i o n of t u n i c
4. Report on e v a l u a t i o n of t u n i c
5. Q u e s t i o n n a i r e for e v a l u a t i o n of o v e r t r o u s e r s
6. Report on evaluation of overtrousers
7. D o c u m e n t a t i o n of d a m a g e d c l o t h i n g
8. G u i d a n c e on l a u n d e r i n g c l o t h i n g
9. G u i d a n c e on r e p a i r i n g d a m a g e
10. S p e c i f i c a t i o n for a n t i - f l a s h h o o d s / p r o t e c t i v e hoods
11. G u i d a n c e on t r a i n i n g in the use of a n t i - f l a s h hoods/
protective hoods
Please check that brigade, contact name and telephone number have been entered on the
front page, and attach continuation sheet(s) and additional documents to the back.
Brigade Details
Brigade :
Brigade Code No
Contact Name :
Telephone :
Number of Firefighters :
F.T.
Ret.
Male Female Total :
Number of Stations :
Whole Day-manned
Retained Volunteer Total Section A : Tunic or One Piece Garment
Al.
Please specify the m a n u f a c t u r e r s and styles of the fire tunics currently on issue in your brigade
Manufacturer
Style
Tunic 1
Tunic 2
Tunic 3
Al.l
Please specify which is your most recent tunic (excluding those on trial)
If you have more than one tunic currently on issue, please answer questions A2 to A6 with
reference to your most recent tunic.
A2.
Does this tunic comply with the A26 specification ?
Y = Yes
N = No
A2.1 If NO, do you plan to buy A26 tunics within the next 1 = Year
2 = 2 Years
3 = 3 Years
4 = More than 3 Years
5 = Not planned
A3.
Do you have any plans to replace your current issue with a different style eg. move to
multi-garment ensembles/multi layered garments/one piece coverall ?
Y = Yes
N = No
Year
A3.1 If YES, please specify when you plan to replace them A4.
1
9
9
Do you have any alterations from the standard style of tunic eg. special equipment
pockets, special fastenings ?
Y = Yes
N = No
A4.1 If YES, please give details (including position) -
Please enclose a copy of your brigade specification for the tunic eg. type of sleeve, fasteners etc.
If you have a photograph of the tunic, could you also enclose it.
Section B : Tunic Sizing
Bl.
Please specify the sizes used and the chest measurements within each size used for
tunic allocation Size
B2.
Chest (inches)
Size
Chest (inches)
Are the tunics ever made to measure for individual firefighters ?
Y
= Yes
N = No
B2.1 If YES, please specify the reasons for this and the measurements taken - for example if the f i r e f i g h t e r
were small, and slim built, the description might be small, and the possible measurements taken migtvt
be, chest, back length and arm length.
Description of
Firefighter
Dimensions taken
chest
back
length
arm
length
Section C : Overtrousers
Please enclose a copy of your brigade specification for the overtrousers used.
If you have a photograph of the overtrousers, could you also enclose it.
Cl.
What specification of overtrousers/leggings is used by your brigade ?
1 = A7
2 = A26 Type
C2.
(Go to C2)
(Go to C3)
When do you plan to introduce overtrousers to a standard comparable with A26 ?
1
2
3
4
5
= Within one year
= In two years
= In 3 years
= In more than 3 years
= Not planned
Now go to Section D C3.
Please specify the m a n u f a c t u r e r and style of the A26 Type overtrousers currently used within
your brigade.
Style
Manufacturer
Section D : Evaluation of Tunics and/or Overtrousers
The A26 specification was published in 1988. If you have replaced your tunic or overtrousers design
since then, or are in the process of evaluating new designs, please complete this section.
If NOT, please tick the not applicable box and go to
Section E.
Dl.
N/A
Please specify the manufacturer and style of tunics and/or overtrousers evaluated or currently
being evaluated Tunic
Manufacturer
Style
Manufacturer
Overtrousers
Style
Evaluation of Tunics
D2.
Please specify the type of evaluation carried out on the tunics
Wearer t r i a l s
Laboratory testing
Other
Y
= Yes
N = No
D2.1 If Other, please specify -
// you answered 1, (wearer trials) please answer D3, otherwise go to D4
D3.
If wearer trials were undertaken were the tunics distributed on 1 = General issue
2 = For specific exercises
D3.1 How many individuals participated in the trials ?
Y = Yes
N = No
D3.2 Did the subjects in the trials complete a questionnaire on tunics ?
// YES, please enclose a copy of the questionnaire used.
D3.3 If NO, please specify what evaluations were made by the subjects -
D4.
Which criteria are used to select the tunics ?
The M a n u f a c t u r e r
Reports from other brigades
Wearer acceptance
Y = Yes
N = No
Physical performance of tunics
Cost
Other
D5.
Have you written an evaluation report on the tunics ?
//" YES, please enclose a copy of the evaluation report.
N = No
Evaluation of Overtrousers
// the overtrousers were either evaluated along with, or by an identical procedure to the
evaluation of the tunics, please tick the box and proceed to D9 - •
D6.
Please specify the type of evaluation carried out on the overtrousers Wearer trials
Laboratory testing
Y = Yes
N = No
Other
D7.
If wearer trials were u n d e r t a k e n were the tunics distributed on 1 = General issue
2 = For specific exercises
D7.1 How many individuals participated in the trials ?
D7.2 Did the subjects in the trials complete a questionnaire on
the overtrousers ?
Y = Yes
N = No
// YES, please enclose a copy of the questionnaire used.
D7.3 If NO, please specify what evaluations were made by the subjects -
D8.
Which criteria are used to select the overtrousers ?
The M a n u f a c t u r e r
Reports from other brigades
Wearer acceptance
Y = Yes
N = No
Physical performance of overtrousers
Cost
Other
D9.
Have you written an evaluation report on the overtrousers ?
// YES, please enclose a copy of the evaluation report.
Y = Yes
N - N
D10. Are you in a purchasing consortium for clothing ?
Y
= Yes
N = No
D10.1 If YES, could you please write down the name and address of the consortium :
Section E : Assessment of the Effects of Wear and Tear
El.
How frequently are the tunics and overtrousers on issue routinely assessed for deterioration in protection.
1
2
3
4
= Less than once per year
= Once per year
= Every 1-3 years
= Every 3 years or more
Tunic
Overtrousers
5 = Never
E2.
What methods are used to assess deterioration ?
E3.
Is the clothing reassessed for deterioration in protection when there are obvious
signs of damage ?
Y = Yes
N = No
E3.1 If YES, please specify what assessments are carried out and what actions are taken ?
E3.2 If NO, please specify what actions are taken -
E4.
Does your brigade use a system of documenting damaged clothing eg.
where the clothing was damaged and in what conditions ?
Y = Yes
N = No
// YES, please enclose examples of the documentation with this Questionnaire.
Section F : Repairing of Tunics and/or Overtrousers
Fl.
If clothing is^damaged, who carries out the repair ?
1
2
3
4
5
= Individual
= Brigade
= Manufacturer
= Dependent on extent of damage
= Other
F1.2 If Other, please specify -
F2
If your answer to the above was number 1, are there any guidelines on the
repair threads/materials etc. to be used ?
Y
N
Yes
No
// YES, please enclose a copy of the guidelines with the questionnaire.
F3.
Is there any inspection/testing of repaired garments to assess whether they still comply with
the brigade specification ?
Y = Yes
N = No
F3.1 If YES, please specify how these assessments are carried out -
Section G : Rank Markings
Gl.
Please specify who is responsible for sewing badges onto tunics ?
1
2
3
4
= Individual
= Brigade
= Manufacturer
= Other
G2.
If Other, please specify -
G3.
If the firefighter is responsible, please specify what guidance is provided concerning the threads
to be used -
Section H: Laundering of garments
HI.
Is the individual firefighter responsible for deciding when to launder
clothing ?
Hl.l
If NO, please specify who is responsible for this decision -
H2.
Do the tunics have to be dry cleaned ?
Y = Yes
N = No
Y = Yes
N = No
H2.1 If NO, are the tunics m a c h i n e washed by A contractor
A station
Y
= Yes
N = No
C e n t r a l l y by the brigade
By the individual wearer
H3.
What criteria are used to define the period between cleaning tunics ?
1 = Specific time interval
2 = N u m b e r of wearings
3 = Dependent on the conditions in which
they have been worn
4 = Combination of above
months
weeks
H3.1 If you answered 1, please specify t i m e period H3.2 If you answered 2, please specify number H3.3 If you answered 3 or 4, please indicate the criteria used -
H4.
Do the overtrousers have to be dry cleaned ?
Y
= Yes
N = No
H4.1 If NO, are the overtrousers machine washed by A contractor
A station
Y = Yes
N = No
Centrally by the brigade
By the i n d i v i d u a l wearer
H5.
What criteria are used to define the period between cleaning 1 = Specific time interval
2 = Number of wearings
3 = Dependent on the conditions in
which they have been worn
4 = Combination of above
months
H5.1 If you answered'l, please specify time period -
H5.2 If you answered 2, please specify n u m b e r -
weeks
H5.3 If you answered 3 or 4, please indicate the criteria used -
Please specify any guidance on laundering provided by the manufacturer or your brigade, for tunics
and overtrousers, either in the box below or on a separate sheet eg. a photocopy of the label.
H6.
Does your brigade make special provision for laundering garments that have been contaminated
with body fluids ?
Y = Yes
N = No
H6.1 If YES, please specify w h a t these special provisions are -
H7.
Are there alternatives to dry c l e a n i n g / m a c h i n e washing for minor soiling ?
Y
N
Yes
No
H7.1 If YES, please specify these alternatives -
H8.
Do you carry out assessments on the effect of laundering on the protection
afforded by the garment ?
Yes
N = No
H8.1 If YES, please specify what assessments are carried out -
H9.
Does your brigade recommend that garments washed together must be
of similar materials ?
Y = Yes
N = No
Section I : Clothing worn with the Tunic and Overt rouseirs
11.
Please specify all the standard personal issue clothing worn by each firefighter-excluding
tunic and overtrousers Clothing worn
Clothing issued Hot weather/Cold weather
Manufacturer
Style
D
D
D
D
D
D
T-shirt
Shirt
Jumper
Trousers
Socks
Shoes
n
n
n
n
Boots
Gloves
Gauntlets
Helmets
D
E
D - D
D
D
D
D
D
D
D
D
n
n
n
n
Anti-flash hoods/
Protect ive hoods
Neckerchief
1— 1
1 1
1 1
'— 1
| |
Any other
D
D
11. 1
n
n
n
1 1
'— '
[ [
If Other, please specify -
12. I s any guidance given on other clothing (including undergarments) that should or should not be worn with
the tunic and overtrousers ?
Y = Yes
N = No
12.1
If YES , please outline -
13. 1s any other protective clothing provided for use in special incidents eg. chemical spillage forest or
ship fires ?
Y = Yes
N = No
13.1
1
2
3
4
If YES , please specify what clothing is provided *
Incident
Clothing Provided
Section J : Anti-flash hoods/protective hoods
By anti-flash hoods or protective hoods we refer to either balaclava styles or looser fitting hoods such as
those designed to the E9 specification.
Jl.
Does your brigade c u r r e n t l y use a n t i - f l a s h hoods or protective hoods ?
Y = Yes
N = No
// YES, please complete questions J2 - J5
If NO, please go to question J6
J2
Please specify the m a n u f a c t u r e r and style of anti-flash hoods or protective hoods used Style
Manufacturer
J3.
When were the anti-flash hoods or protective hoods introduced ?
1 = Less than 6 months ago
2 = 6-12 months ago
3 = More than 12 months ago
J3.1
If your answer to the above question was 3, please specify the year -
Please enclose a copy of your brigade specification for the anti-flash
hoods/protective hoods
J4.
J5.
Please list any operational tasks in which you advise f i r e f i g h t e r s to wear anti-flash hoods/
protective hoods and the typical duration of these tasks Duration :
Task :
^__^
Task :
Hrs
Mins
A
B
B
C
C
D
D
Please list any t r a i n i n g exercises in which you advise firefighters to wear anti-flash hoods/protective
hoods and the typical duration of these tasks Duration :
Task :
A
Task
B
B
C
C
D
D
Hrs
A
// YES, please enclose any guidance notes on training or a brief summary
on the sheet provided.
Go to Section K
Mins
Questions J6 to J7 for those who do not currently use anti-flash hoods J6.
As you do not have anti-flash hoods, are you currently evaluating the use of anti-flash
hoods/protective hoods ?
Y = Yes
N = No
J6.1
if YES, please specify the manufacturer and style Style
Manufacturer
J7.
Will you introduce anti-flash hoods/protective hoods to the brigade in ?
1 = Less than 6 months
2 = 6-12 months
3 = More than 12 months
Section K : Breathing Apparatus
In the questionnaire from the study of the physiological effects of wearing Breathing Apparatus
sent to your brigade in February 1991, it was stated that the set used by your brigade was :
B.A. Set
Y = Yes
N = No
Kl.
Is this still the B.A. set used ?
Kl.l
If NO, please specify the B.A. set currently used within your brigade Manufacturer
Model
K1.2 If YES, please indicate when the set is due for replacement 1 = Within 1 year
2 = Within 1-3 years
3 = In 3 years or more
Can you please ensure you have completed the checklist. Thank you for completing this
Questionnaire.
Summary
APPENDIX B
Firefighters Questionnaire
The Protection Afforded by Firefighters' Protective Clothing
Operational Firefighters Questionnaire
Instructions
This questionnaire is part of a three year study commissioned by the Home Office on the degree of protection
afforded by firefighters' protective clothing. This questionnaire is intended to identify the opinions of
individual firefighters on their clothing and any equipment that is used in combination
with
the clothing. The results will be used to assess ways in which the comfort, design and protection of the
clothing could be improved. Any information you do give us will be treated confidentially and individual
responses will not be reported. To ensure this, you should have received a reply paid envelope with this
questionnaire. If you have not received an envelope and would like one, please contact us on the telephone
number provided.
The questionnaire has been divided into 12 sections each dealing with a specific aspect of the clothing, and
the interactions between the clothing and equipment.
There are four different types of question in the questionnaire. An example of each is shown below.
1. For questions with Yes/No answers, please write a Y or N in the box provided,
Y = Yes
N = No
eg. Do the cuffs have thumb loops ?
2. For questions with multiple choice answers please enter the appropriate number in the box provided,
eg. C2. Do you think that the weight of the clothing is :
1. very light
2. light
3. average
4. heavy
5. very heavy
3. For questions asking about details of the manufacturer and specification/standard, the answers
should be written in the table provided.
eg. Section B - Description of clothing
Manufacturer
Tunic
Approx.
Age
Yrs.
Mths.
Specification/Standard
iomoi3
Overtrousers/
leggings
Working Rig:
Trousers
T-Shirt
Boiler suit
J I
I
I
I I
No. on
Personal
Issue
4. The fourth type of question asks you to provide detailed explanations about/or your own comments
on the problems that may arise with the clothing. These should be written in the box provided
below the question.
eg. ES. If you answered NO to Question 4, please specify how the collar is inadequate -
5. If a question does not apply to you can you please write not applicable in the space provided.
If you have any queries about the questionnaire or the questions asked, please contact Miss Julia
Johnstone, or Ms Joanne Crawford at the Institute of Occupational Medicine on 031-667 5131
Extension 2514.
It would be most useful if this questionnaire could be completed by Friday 28th August,
then returned to the Institute of Occupational Medicine, 8 Roxburgh Place, Edinburgh EH8 9SU.
However, we would much prefer to receive the questionnaire late rather than never.
Thank you for your co-operation
Section A : Background Information
Name :
Rank :
Brigade Number :
Yr s
1" ths
Length of service :
Brigade :
Watch :
F or R
Are you a Full-time or a Retained firefighter ?
Day
Today's Date:
Section B : Clothing
Manufacturer
This section should cover all clothing worn with the A26 tunics.
Please describe your most recent issue.
Approx.
No. on
Age
Personal
Specification/Standard
Yrs.
Mths.
Issue
Tunic
Overtrousers/
leggings
Working Rig:
Trousers
T-Shirt
Coveralls
Undress uniform:
Trousers
Shirt
Boiler suit
Helmet
Gloves
Gauntlets
Anti-flash hood/
Protective hood
Section C : Weight and size of clothing
This section is concerned with the acceptability of outer wear ie. the two piece tunic and overtrousers,
or the one piece ensemble.
Cl.
Have you always worn the A26 specification clothing ?
C2.
How would you describe the weight of the clothing ?
1
2
3
4
5
=
=
=
=
=
very light
light
average
heavy
very heavy
Y = Yes
N = No
C3.
Do you find the clothing too bulky ?
Y = Yes
N = No
C4.
When being used operationally, do you find the clothing too bulky ?
Y = Yes
N = No
C5a. Does the clothing restrict your movement when you reach upward ?
Y = Yes
N = No
C5b. Does the clothing restrict your movement when you reach forward ?
Y = Yes
N = No
C5c. Does the clothing restrict your movement when you reach down ?
Y = Yes
N = No
C6.
If YES to any of the above, please specify where the restrictions occur, and what causes
the restrictions - eg. site: underarm, cause: tight sleeve when climbing ladders
Site of Restriction
Cause of Restriction
1.
2.
3.
C7.
Any f u r t h e r comments on the weight and size of the clothing -
Section D : Comfort of Tunic/Overtrousers
Dl.
How comfortable do you find the tunic ?
1 = very comfortable
2 = comfortable
3 = slightly uncomfortable
4 = very uncomfortable
D2.
If you find the tunic uncomfortable, please specify what causes the discomfort -
D3.
How comfortable do you find the overtrousers/leggings ?
1 = very comfortable
2 = comfortable
3 = slightly uncomfortable
4 = very uncomfortable
D4.
If you find the overtrousers/leggings uncomfortable, please specify what causes the
discomfort -
D5.
When you are working hard, how sweaty do you get in your tunic ?
1 = not sweaty
2 = slightly sweaty
3 = very sweaty
D6.
When working in hot conditions, how hot does the surface of the tunic get ?
1 = no heat trapped
2 = some heat trapped
3 = a lot of heat trapped
D7.
After exiting from a fire incident, how hot does your tunic remain ie. how much heat is
retained in the tunic ?
1 = no heat retained
2 = some heat retained
3 = a lot of heat retained
D8.
When you are working hard, how sweaty do you get in your overtrousers ?
1 = not sweaty
2 = slightly sweaty
3 = very sweaty
D9.
When working in hot conditions, how hot do your overtrousers/leggings get, ie. how much
heat is trapped in the overtrousers/leggings ?
1 = no heat trapped
2 = some heat trapped
3 = a lot of heat trapped
D10. After exiting from a fire incident, how hot do your overtrousers/leggings remain,
ie. how much heat is retained in the overtrousers/leggings ?
1 = no heat retained
2 = some heat retained
3 = a lot of heat retained
Dll.
Any further comments on the comfort of the tunic or overtrousers/leggings ?
Section E : Protection afforded by the tunic and overtrousers or one piece
ensemble
El.
Do the cuffs on your t u n i c have thumb loops ?
Y = Yes
N = No
B2.
Do the cuffs on your tunic provide adequate protection against heat exposure ?
Y = Yes
N = No
E3.
If no, please specify how the cuffs are inadequate -
E4.
Does the collar provide adequate protection against heat exposure ?
Y = Yes
N = No
E5.
If NO, please specify how the collar is inadequate -
E6.
Does the tunic provide adequate protection against radiant heat ?
Y = Yes
N = No
E7.
If NO, please specify which parts of the tunic are inadequate -
E8.
When you are crawling, does your clothing move to expose any body parts ?
Y = Yes
N = No
E9.
If YES, please specify -
E10. When reaching up, (eg. when climbing a ladder), does a gap develop between the cuff and
the glove ?
Y = Yes
N = No
Ell.
When crouching, does a gap develop between your overtrousers or leggings and boots ?
Y = Yes
N = No
C12. Do you have any other problems with your clothing moving to expose body parts ?
Y = Yes
N = No
E13. If YES, please specify what the problems are -
E14. During t r a i n i n g or operational situations have you ever been told to "dress up" eg. don E9 anti-flash
hood or "dress down" ie. removing a layer of clothing eg. when attending a grass fire ?
Y = Yes
N = No
E15 If YES, please specify the circumstances and the actions taken -
E16. Any further comments on the protection afforded by the tunic or overtrousers/leggings -
Section F : Anti-Plash Hoods/Protective Hoods
By anti-flash hoods/protective hoods, we refer to either balaclava styles or the looser f i t t i n g
hoods such as those designed to the E9 specification.
Fl.
Do you t h i n k anti-flash hoods/protective hoods are a good idea ?
Y = Yes
N = No
F2.
Have you been issued with an anti-flash hood/protective hood ?
Y = Yes
N = No
// NO, please go on to Section G.
F3.
How sweaty do you get when wearing an anti-flash hood ?
1 = not sweaty
2 = slightly sweaty
3 = very sweaty
F4.
Do you t h i n k that the anti-flash hood/protective hood affects your ability to hear ?
1 = not at all
2 = slightly affected
3 = greatly affected
F5.
Does the anti-flash hood/protective hood cause any problems when worn with other protective
equipment ?
Y = Yes
N = No
F6.
F7.
Do you feel that the anti-flash hood/protective hood isolates you too much from the
heat ?
Y = Yes
N = No
F8.
If YES, please describe -
F9.
Do you have any other problems with your anti-flash hood/protective hood ?
Y = Yes
N = No
F10. If YES, please describe -
Fll.
Did you have any training in the use of your anti-flash hood/protective hood ?
Y = Yes
N = No
Flla If YES, did the training include the interaction between the use of hood and B.A. ?
Y = Yes
N = No
F12
During which training exercises do you wear your anti-flash hood/protective hood ?
1
2.
3.
4.
F13. Do you wear an anti-flash hood/protective hood with B.A. ?
Y = Yes
N = No
F14. Do you wear an anti-flash hood/protective hood during any other operations ?
Y = Yes
N = No
F14a If YES, please specify -
F15. Given a free choice would you wear an anti-flash hood/protective hood ?
Y = Yes
N = No
F16. Any f u r t h e r comments on anti-flash hoods/protective hoods -
Section G : Gloves and other Personal Issue Equipment
By personal issue equipment we mean
radios, torches, personal lines etc.
Gl.
Do you f i n d it easy to tuck your gloves inside the sleeves of the tunic ?
Y = Yes
N = No
G2.
If NO, can you suggest a way in which this could be improved -
G3.
Do you find it easy to tuck your gauntlets inside the sleeves of your tunic ?
Y = Yes
N = No
G4.
If NO, can you suggest a way in which this could be improved ?
G5.
Does any of your personal issue equipment eg. radio, cause problems with your clothing ?
Y = Yes
N = No
G6.
G7.
Any f u r t h e r comments on interactions with other personal issue equipment -
Section H : Damage to Garments
HI.
If your tunic or overtrousers are damaged, who carries out the repair ?
1 = myself
2 = others
3 = dependent on damage
H2.
If 2 or 3, please specify who is responsible for the repair ?
H3.
Have any of your current personal issue garments been damaged ?
Y = Yes
N = No
H4.
If YBS, please specify where on the garment(s) and how the damage occurred -
H5.
Are the reflective strips on the tunics ever replaced ?
Y = Yes
N = No
H6.
If YES, is the replacement of the reflective strips 1 = periodic
2 = dependent on damage
H7.
Do you decide if your clothing should be replaced ?
Y = Yes
N = No
H8.
If NO, please specify who decides -
H9.
Any further comments on damage to garments -
Section I : Laundering/Storage of Clothing
II.
How often do you have your overtrousers laundered/dry cleaned ?
1 = more than once per month
2 = monthly
3 = less than once per month
4 = as required
12.
Do you have a detachable lining in your tunic ?
Y = Yes
N = No
13.
If YES, how frequently do you launder the lining ?
2 = monthly
4 = as required
14.
How often do you have your tunic laundered ?
2 = monthly
15.
4 = as required
How often do you have to wear a damp tunic to a call-out ?
1 = 4 or more times per week
2 = 2 to 3 times per week
3 = once per week
4 = 2-3 times per week
5 = once per month
If NEVER, go to question 17
16.
If you have worn a damp tunic, please specify the degree of heat build-up ?
1 = no heat build-up
2 = slight heat build-up
3 = some heat build-up
4 = considerable heat build-up
I6a.
Did you have to leave the incident earlier than you would have done with a dry uniform ?
Y = Yes
N = No
I6b
If YES, please specify the conditions in which this occurred -
17.
Please specify how a wet tunic is dried on return to the station -
18.
Please specify how dry tunics are stored -
19.
During the winter months, does your tunic provide adequate insulation against the cold ?
Y = Yes
N = No
110.
Any f u r t h e r comments on laundering/storage of tunics ?
Section J : Breathing Apparatus
Jl.
Please specify the B.A. you use Manufacturer
J2.
Model
IOM use only
Do the straps of the B.A. sets cover any pockets on your tunic ?
Y = Yes
N = No
J3.
If YES, is any equipment normally carried in these pockets ?
Y = Yes
N = No
J4.
If YES, please specify in which pockets equipment is carried and what equipment -
J5.
Do you remove the equipment from the pockets before using a B.A. set ?
Y = Yes
N = No
J6.
Any further comments on breathing apparatus -
Section K : Injuries
Kl.
Have you ever had a scald or burn injury during an operational incident ?
Y = Yes
N = No
K2.
001103
Have you ever had a scald or burn injury during training ?
Y = Yes
N = No
K3.
K4.
K4.
If YBS, to either Kl or K2 do you feel that changes to the clothing could have reduced or
prevented the injury ?
Y = Yes
N = No
If YES, please specify which items of clothing provided inadequate protection and in which
way it was inadequate -
Any f u r t h e r comments on injuries -
Section L : Work and Training Scenarios
LI.
During TRAINING, which task did you find the most physically demanding when
not using B.A. ?
12.
During OPERATIONAL INCIDENTS, which task did you find the most physically
demanding when not using B.A. ?
L3.
Which was the more physically demanding of the two described above ?
1 = training
2 = operational
L4.
Please describe any work and/or training which has not been physically demanding but
where you have become too hot/cold -
Thank you for completing this questionnaire.
APPENDIX C
Fitting Trial Questionnaire
Study of the Interaction Between Protective Hood, Helmet and BA
Name of Subject:
Subject Code:
Trial Week:
Date of Test:
Hood Worn:
Section A: Working When Wearing Protective Hood and Helmet
Al. How easy or difficult did you find putting on the protective
hood?
1 = No difficulty
2 = Minor difficulty
3 = Major difficulty
A2. How easy or difficult did you find putting on the helmet with
the protective hood?
1 = No difficulty
Researcher - Check Position of Protective Hood on Head, is hood
fitted correctly around neck and ears?
MOVING HEAD FORWARDS
A3. When moving your head forwards did you find that the protective
hood moved out of position?
Y = Yes
N = No
A4. When moving your head forwards did you find that your helmet
moved out of position?
Y = Yes
N = No
A5. When moving your head forwards did the yoke on the protective
hood restrict your movements?
Y = Yes
N = No
A5.1. If yes, where did the restrictions occur?
A6. When moving your head forwards did you find any part of your
equipment caused discomfort?
Y = Yes
N = No
A6.1 If yes, please specify what caused the discomfort.
Researcher - check if hood position has changed, if so please write
down the change e.g. yoke moved out of position or ear holes moved.
MOVING HEAD LEFT AND RIGHT
A7. When moving your head left and right did you find that the
protective hood moved out of position?
Y = Yes
N = No
A8. When moving your head left and right did you find that your
helmet moved out of position?
Y = Yes
N = No
A9. When moving your head left and right did the yoke on the
protective hood restrict your movements?
Y = Yes
N = No
AlO. When moving your head left and right did you find any part of
your equipment caused discomfort?
Y = Yes
N = No
TILTING HEAD SIDEWAYS
All. When tilting your head sideways did you
find
that
the
Y = Yes
N = No
A12. When tilting your head sideways did you find that your helmet
Y = Yes
N = No
A13. When tilting your head sideways did the yoke on the protective
Y = Yes
N = No
A14. When tilting your head sideways did you find any part of your
Y = Yes
N = No
TILTING HEAD BACKWARDS
A15. When tilting your head backwards
did you find that the
Y = Yes
N = No
A16. When tilting your head backwards did you find that your helmet
Y = Yes
N = No
A17. When tilting your head backwards
did
the
yoke
on
the
Y = Yes
N = No
A18. When tilting your head backwards did you find any part of your
Y = Yes
N = No
CARRYING OUT TASKS
A19 When you were carrying out the tasks did you find that the
protective hood moved?
Y = Yes
N = No
A19.1 If yes, please specify what movements caused this (e.g.
bending forwards).
A20. When carrying out the tasks were you ever aware that your
helmet moved?
Y = Yes
N = No
A20.1 If yes, please specify what movements caused this
bending forwards).
(e.g.
A21. When carrying out the tasks were you aware of any gaps
occuring between the protective hood and the BA mask?
Y = Yes
N = No
A21.1 If yes, please describe where the gaps occured
A22. When carrying out the tasks were you aware of the protective
hood causing any restrictions on your movement?
Y = Yes
N = No
A22.1 If yes, where did the restrictions occur?
SECTION B: WORKING WHEN WEARING PROTECTIVE HOOD, HELMET AND BA
Bl. How easy or difficult did you find putting on the protective
hood over the BA mask?
1 = No difficulty
B2. Did the straps on the BA mask loosen when you put on the
protective hood?
1 = Yes
N = No
B3. How easy or difficult did you find putting on the helmet with
the protective hood and BA mask?
1 = No difficulty
MOVING HEAD FORWARDS
B4. When moving your head forwards did you find that the protective
hood moved out of position?
Y = Yes
N = No
B5. When moving your head forwards did you find that your helmet
Y = Yes
N = No
B6. When moving your head forwards did your find your BA mask
movedout of position?
Y = Yes
N = No
B7. When moving your head forwards did you have any gaps between
your protective hood and the BA mask?
Y = Yes
N = No
B7.1 If yes, where did the gaps occur?
B8. When moving your head forwards did the yoke on the protective
Y = Yes
N = No
B8.1. If yes, where did the restrictions occur?
B9. When moving your head forwards did you find any part of your
Y = Yes
N = No
B9.1 If yes, please specify what caused the discomfort.
MOVING HEAD LEFT/RIGHT
BIO. When moving your head left and right did you find that the
Y = Yes
N = No
Bll. When moving your head left and right did you find that your
Y = Yes
N = No
B12. When moving your head left and right did your find your BA
mask movedout of position?
Y = Yes
N = No
B13. When moving your head left and right did you have any gaps
between your protective hood and the BA mask?
Y = Yes
N = No
B14. When moving your head left and right did the yoke on the
Y = Yes
N = No
B15. When moving your head left and right did you find any part of
Y = Yes
N = No
TILTING HEAD SIDEWAYS
B16. When tilting your head sideways
did
you
find
that
the
Y = Yes
N = No
B17. When tilting your head sideways did you find that your helmet
Y = Yes
N = No
B18. When tilting your head sideways did your find your BA mask
movedout of position?
Y = Yes
N = No
B19. When tilting your head sideways did you have any gaps between
Y = Yes
N = No
B20. When tilting your head sideways did the yoke on the protective
Y = Yes
N = No
B21. When tilting your head sideways did you find any part of your
Y = Yes
N = No
TILTING HEAD BACKWARDS
B22. When tilting your head backwards
did you
find that
the
Y = Yes
N = No
B23. When tilting your head backwards did you find that your helmet
Y = Yes
N = No
B24. When tilting your head backwards did your find your BA mask
Y = Yes
N = No
B25. When tilting your head backwards did you have any gaps between
Y = Yes
N = No
B26. When tilting your head backwards
did
the
Y = Yes
N = No
yoke
on
the
B27. When tilting your head backwards did you find any part of your
Y = Yes
N = No
CHECKING CYLINDER GAUGE
B28. When checking your cylinder gauge did you find that the
Y = Yes
N = No
B29. When checking your cylinder gauge did you find that your
Y = Yes
N = No
B30. When checking your cylinder gauge did your find your BA mask
Y = Yes
N = No
B31. When checking your cylinder gauge did you have any gaps
between your protective hood and the BA mask?
Y = Yes
N = No
B32. When checking your cylinder gauge did
the yoke
Y = Yes
N = No
on
the
B33. When checking your cylinder gauge did you find any part of
Y = Yes
N = No
CARRYING OUT TASKS
B34. When carrying out the tasks did
you
find that
the
Y = Yes
N = No
B34.1 If yes, please specify what movements caused this (e.g.
bending forwards).
B35. When carrying out the tasks were you ever aware that your
helmet moved?
Y = Yes
N = No
B35.1 If yes, please specify what movements caused this (e.g.
bending forwards).
B36. When carrying out the tasks were you aware of any gaps
occuring between the protective hood and the BA mask?
Y = Yes
N = No
B36.1 If yes, please describe where the gaps occured
ft..
B37. When carrying out the tasks were you aware of the protective
hood causing any restrictions on your movement?
Y = Yes
N = No
B37.1 If yes, where did the restrictions occur?
APPENDIX D
Training Exercises Questionnaire
and Study Schedule
Protective Hood Wearer Trials
Trial Participants Questionnaire
These wearer trials form part of a study commissioned by the Home Office
investigating the use of protective hoods within the Fire Service. The
results of the study will contribute to a Home Office review of this area,
all information will be treated confidentially and individual responses will
not be reported.
There are three different types of question in the questionnaire. An example
of each is shown below.
1. For questions with Yes/No answers, please place a tick in the appropriate
box provided, e.g.
Have you previously worn a protective hood
during fire fighting operations or exercises ?
Yes
No
This type of question also has a space for you to expand your answer
if desired, e.g. ( for the question above ).
// YES, please explain :
I had a PUC hood on trial for 3 months and used it for all fire fighting
duties.
2. For questions that ask you to indicate whether you agree or disagree with a
statement, please select a response from the scale adjacent to the statement
and write its number in the box provided, e.g.
Fire hoods provide essential additional
protection.
1. Agree
2. Disagree
3. No opinion
3. For questions that ask you to select your answer from a list of possible
alternatives, please select your answer and place its corresponding number
in the box provided, e.g.
1. Very easy
2. Quite easy
3. Quite difficult
4. Very difficult
Section A : Background Information
IOM use only:
Personal details :
Surname :
Male
Sex:
Female
Day
Mth
Yr
Date of Birth :
Rank :
Brigade :
Yrs
Mths
Length of Service :
Full:
Are you a full-time or a retained
firefighter ?
Retained :
Details of training course
Title of course :
Site of course (Name of Training
Centre) :
Day
Mth
Yr
Start date of course :
Details of course exercises for which a fire hood was used :
Time
Date
Description of Task
Day
Mth
Yr a.m.
Exercise 1.
p.m.
Exercise 2.
Exercise 3.
Exercise 4.
Exercise 5.
Exercise 6.
Make of Fire Hood to be used during course
(Examine manufacturers label and tick one
box only).
Cairns and Brother Nomex.
(Plain white balaclava).
Cairns and Brother PBi/Rayon.
(Plain brown balaclava).
Diktron Developments Ltd Nomex III.
(Cream, single-ply hood, with sewn-in
'diamond-shaped', perforated ear
pieces).
Heathcoat Fabrics Kennel.
(Blue, dual-ply hood, no ear holes).
Mattisons 'Proban'.
(Blue, flanelette hood, with sewn-in
perforated ear pieces).
PUC Kermel/Viscose.
(Blue, dual-ply hood with ear holes
through inner layer).
Rhone Poulenc Kermel.
(White, dual-ply hood of knitted material,
brown stripe denotes inside surface of
hood).
Warm'n Dry Kermel/Viscose.
(Blue, single-ply hood with 'fluffy', inside
surface).
Section B : Experience and knowledge of fire hoods
1. Have you previously worn a fire hood during fire
fighting operations or exercises ?
Yes
(Do not include experience of wearing the E9
'Beekeeper', in your answer)
No
// Yes, please give details of any experience you have had :
2. Have you received any guidance or advice about working
whilst wearing a protective hood ?
Yes
No
// Yes, please comment on any guidance you have had:
3. Do you hold an opinion regarding the supposed advantages
and disadvantages associated with wearing fire hoods for
fire fighting activities ?
// Yes, what is your opinion :
yes
j^0
The statements below refer to your current feelings about the use of fire hoods. These
may be based on personal experience, material that you have read, or reports from colleagues
or other firefighters. Please indicate whether you agree or disagree with each statement
by selecting a response from the adjacent scale and writing its number in the box provided.
4. Fire hoods provide essential additional protection.
1 Agree
2. Disagree
3. No opinion
5. Fire hoods remove vital sensory contact with
the environment.
1. Agree
2. Disagree
3. No opinion
6. Wearing a fire hood makes the firefighter feel
too isolated from the heat.
1. Agree
2. Disagree
3. No opinion
7. Fire hoods do not affect your ability to hear.
1. Agree
2. Disagree
3. No opinion
8. Firefighters who wear fire hoods are overprotected. 1- Agree
2. Disagree
3. No opinion
If you would like to make any other comments about fire hoods at this stage, please put
them in the box provided below :
Do not answer any further questions at this stage.
Section C: Headgear
1. Did you encounter any difficulties when using the
fire hood with your B.A. mask ? e.g. Fire hood
causing B.A. mask straps to loosen when being
pulled into position, hood restricting vision through
the B.A. mask facepiece, etc.
yes
jô
// Yes, please describe any difficulties that you encountered:
2. Did you encounter any difficulties when using
the fire hood with your helmet ? e.g. fire hood
helmet to slip out of position, etc.
.,
// Yes, please describe any difficulties that you encountered
Did the fire hood fit snugly on your head and
tightly around your B.A. mask ?
Yes
No
If No, please indicate areas where the fit was poor by shading the diagram below
and add explanatory notes, e.g. too loose, too tight, etc.
4. Does your firefighters helmet have a protective
skirt (also known as a neck curtain or 'earlaps'),
fitted to it ?
Yes
No
5. Was it in the deployed position during the exercise/s ?
Yes
No
6. Do you think it is important to be wearing both
a protective hood and a helmet skirt in a live
fire situation, or would one or the other suffice ?
Please comment on your answer
1. Hood or skirt
2. Hood only
3. Skirt only
4. Hood and skirt
5. Neither
Section D: Wearability
For this section please select the statement that most closely matches your answer and
write its number in the box provided.
1. How easy or difficult was it to put on the
fire hood ?
1. Very easy
2. Quite easy
3. Quite difficult
4. Very difficult
2. Do you think wearing a fire hood affected your normal perspiration rate
during the exercise/s ?
1. Greatly reduced perspiration rate
2. Slightly reduced perspiration rate
3. No effect
4. Slightly increased perspiration rate
5. Greatly increased perspiration rate
3. Do you think wearing a fire hood affected how hot you felt during the
exercise/s ?
, „ ,.
,
,
1. Felt much cooler
2. Felt slightly cooler
3. No effect
4. Felt slightly hotter
5. Felt much hotter
4. How comfortable was the fire hood to wear ?
1. Very comfortable
2. Comfortable
3. Uncomfortable
4. Very uncomfortable
5. Do you think that having to wear a fire hood affected your ability
1. Greatly reduced hearing ability
2. Slightly reduced hearing ability
3. No effect
4. Slightly improved hearing ability
5. Greatly improved hearing ability
6. Did the protective hood cause any problems or inconvenience Yes
by interfering with fire kit or any other equipment ?
No
e.g. causing difficulty in fastening helmet strap, hood getting
caught in tunic zip and causing it to jam, etc.
// Yes, please describe any problems that occurred:
The two questions below should only be completed by wearers trialling the Diktron
Mattisons and PUC hoods.
7. When your fire hood was comfortably and correctly
fitted did the ear holes/perforated ear pieces align
with your ears ?
Yes
No
Please comment on the positioning of the ear holes/perforated ear pieces :
8. Do you think it is useful to have features like ear
holes (PUC hoods) or perforated ear pieces (Diktron
and Mattisons hoods) incorporated in the design
of fire hoods ?
Yes
No
Please comment on the usefulness of ear holes/perforated ear pieces
Section E : Attitudes towards fire hoods
1. Are you/would you be happy to wear a fire
hood for firefighting operations ?
Yes
2. Would you be happy to wear this fire hood
for firefighting operations ?
Yes
No
No
If NO, please explain why not:
For each of the following statements please select a score from the scale that matches
your level of agreement/disagreement with the statement.
3. I felt much better protected as a result of wearing 1. Agree
the fire hood.
2. Disagree
3. No opinion
4. I felt too isolated during the exercise/s because I
was wearing the fire hood.
1. Agree
2. Disagree
3. No opinion
5. Wearing the fire hood allowed me to get closer
to the fire.
1. Agree
2. Disagree
3. No opinion
6. Wearing the fire hood made me feel less confident 1. Agree
about the state of the surrounding environment.
2. Disagree
3. No opinion
7. My ability to carry out the exercise/s was
completely unaffected by wearing the fire
hood.
1. Agree
2. Disagree
3. No opinion
8. I cannot think of any firefighting situation
when I would choose to wear a fire hood.
1. Agree
2. Disagree
3. No opinion
9. I think that deciding when to wear a fire hood
should be left to the discretion of the individual
firefighter.
1. Agree
2. Disagree
3. No opinion
If you would like to make any additional comments about fire hoods and their use,
please put them in the box below :
Thank you for participating in this study.
FIRE HOOD WEARER TRIALS
STUDY SCHEDULE
1.
Beginning of course - hoods, questionnaires,
and other materials distributed by the course
instructor.
2.
Read the 'Guidance notes', and the instructions
on the front of the questionnaire.
3.
Complete Sections A and B of the questionnaire
and familiarise yourselves with the content of
the remaining sections.
4.
Make sure you know how to fit a fire hood
correctly by referring to the 'How to fit a fire
hood', instruction sheet.
5.
Wear the fire hood whilst taking part in the
exercises that comprise the course.
6.
At the end of the course complete the
remaining sections of the questionnaire.
7.
Return the hoods and the completed
questionnaires to the course instructor.
8.
End of the wearer trial.
GUIDANCE NOTES FOR FIRE-FIGHTERS PARTICIPATING IN THE
There is some debate within the Fire Service at present regarding the advantages and disadvantages
of wearing a fire hood during fire fighting activities. The purpose of these wearer trials is to establish
the attitudes and reactions of both current and future wearers to the use of these hoods. A further
objective is to examine the fire hoods currently available for use and attempt to determine whether
any particular hood is superior in terms of comfort, insulation, ease of use or any other properties
that may become apparent during the course of these trials.
Together with these guidance notes your course instructor should have issued you with the following
items :
1)
2)
3)
A questionnaire.
A fire hood.
An instruction sheet explaining how to fit a fire hood correctly.
To assist the smooth running of this study your course instructor will display a study schedule giving
a step by step guide to the wearer trials.
Before attempting to answer any of the questions in the questionnaire first read the instructions given
on the coversheet, then complete Sections A and B only. Your course instructor will give you details
of the course title and of the exercises the course comprises. Inspecting the manufacturers label will
help you to identify the make of hood that you have been issued with.
Once you have completed Section A and B, please examine the remaining sections of the
questionnaire and familiarise yourself with their content but do not answer any other questions at this
stage.
Before using the fire hood that you have been issued with, make sure that you know how to fit it
correctly by referring to the 'How to fit a fire hood', instruction sheet.
When you are using the fire hood be sensitive to the effect that the hood may be having on your
comfort, behaviour, and the ease with which you would expect to carry out the exercise/s. For
example, if you had some difficulty in fastening your helmet strap and you felt that this was due to
having to wear a fire hood, then report the difficulty in your answers to the questionnaire. Any
observation of this type is likely to be of interest to us.
When answering questions please be as thorough as possible and make full use of the spaces provided
for explaining your answers, using the backs of the pages if necessary.
Please do not discuss questions with your colleagues as it is important that your answers only reflect
your own views and not those of others.
Finally, please make sure that your fire hood and the completed questionnaire are returned to the
course instructor once your course has finished.
Thank you for agreeing to participate in this study. If you have any queries or anything
regarding the use of fire hoods that you would like to discuss, please contact Mr Dominic Butler
at the Institute of Occupational Medicine. Tel : (0131) 667-5131 Ext 2401.
How to fit a fire hood
1) Put the fire hood on over your head.
2) Tuck the fire hood yoke inside the
collar of your tunic.
3) Pull the fire hood down around your
neck, put on your BA mask, then pull
the fire hood up over the mask.
4) The fire hood should fit snugly under
the demand valve and around the
sides and top of your mask face piece.
APPENDIX E
Observational Trials: Questionnaires and Recording Sheets
(To be completedfor subjects undertaking all conditions)
Name:
Subject No:
Condition being undertaken:
Please sketch a plan of the house as you recall it. If possible show the placement of doors and
obstacles/furniture. Please mark the position(s) of the heat source(s).
Ground Floor
1st Floor
(To be completedfor subjects undertaking all conditions}
Objective Measurements
(Please attach control room temperature sheet)
Name:
Subject No:
Brigade:
No of years experience:
Use of fire-hoods:
habitual / sometimes / not at all
Condition being undertaken:
control / hood / skirt / hood & skirt
(1)
Timings, (obtained from control room operator):
[a]
Entry - bottom of stairs
min
sec
[b]
Startof stairs - 1st floor entry door
min
sec
[c]
Entry of 1st floor door -bedroom door
min
sec
[d]
Bedroom search (door to door)
min
sec
[e]
Exit (from bedroom door to final exit)
min
sec
(2)
No of gouge checks
(3)
Crouching at doors?
(4)
Ascending / Descending of stairs?
(5)
Search Patterns ? (tri*ing on obstacles, checking of cupboards etc)
(To be completed only by subjects undertaking the hood, skirt, or hood & skirt conditions)
Name:
Subject No:
Condition Undertaken:
Hood / skirt / hood & skirt
(Please tick the appropriate box)
Yes
No
(1)
Did the hood/skirt make you feel isolated from the environment?
[ ]
[ ]
(2)
Did the hood reduce your awareness of the temperature you were
exposed to?
[ ]
[ ]
(3)
Did you find your hearing was reduced by wearing a hood/skirt?
[ ]
[ ]
(4)
Did the hood interfere with communication?
[ ]
[ ]
(5)
Did you find it harder to locate the source of noises when wearing
a hood/skirt?
[ ]
[ ]
[ ]
[ ]
(6)
How much protection did the fire-hood provide during the exercise:
too much
about right
Too little
(7)
[ ]
f ]
[ ]
Do you think that fire-hoods are a good idea?
If No, please specify why not....
Firehouse Exercise Log
Date of test:
Name of subject:
Start time in zone 1 :
Start time in zone 2:
Start time in zone 3 :
Time 0.<*
I»WESW
^
iMr-
Endtime:
Endtime:
Endtime:
Endtime:
Endtime:
0.10
405
im
•
.: OilS
:«% " ^-":;
OJS
s
^
^
%
î .
• \ • ^.
•
^ ^ ™?
\
*•
v %S S S\
\ N^ ;\ " S \ S«v. 0
™ % * i\ : ^-^ ^ o^
%s!%
%
i.sSs^"" °™
1^&
XS^x^ \s««x
v "° s\ s«;
%%%« \is\
^"V
;;:; ^
"c-^4.-ivfcvNtt. \
s
:SS&
%
^
• «*M" ^
ÔiLf
!**&>.
\5v ^« O5
v
%
" :
%
;
s %%
"^
' ,^
"•
: A.V»«« * ••••5 ^ *
r<
S\ 5
•Avftv^sv
i
s« %"s^0 ~S;
« «" ; \ , r^ ™" ; 5;
"•
[&**^
u%
",•••• ••" i
v ^
,$£4 H ---- s - 5 -
v" •• ^
L^
^ '•'•V-i."l-" \"
%
v^V
0^
" :„£&•£••
;sss
\ •- j. v
, " -.
%i
5 «..•.•• vv;«--;5~;
rr ••••" *
s,-ir.!..s \\Wrn... ;
%
-
-
;
1
^ \
%
\%
:««s^x
; i ?;\sv^ •• i
5 5
i^K-: ^ 1 •• ^"\ \ " ^ \:
APPENDIX F
Signal Direction Record Sheet
Firefighter:
Hood:
Set: 1 or
2
Date:
Time:
©
©
(4) ©
1
7
§
10©
®11 ©
®12
APPENDIX G
Physiological Trials Questionnaires
Treadmill Exercise (Control)
Name of Subject:
Date of Test:
Test No:
1. During the exercise were you aware that your helmet moved out of position?
Yes
No
2. During the exercise did you ever find your BA mask moved out of position?
Yes
No
3. During the exercise did any part of your equipment cause you discomfort?
Yes
No
If yes, please specify what caused the discomfort:
4. During the exercise how hot did you feel overall?
Cool
Neither hot nor cold
Warm
Hot
Extremely hot
5. During the exercise how hot did your head feel?
Cool
Warm
Hot
Extremely hot
6. If you have any other comments about the equipment you wore during the exercise, please use the
space below:
Thank you for your help.
Treadmill Exercise Wearing a Protective Hood
Name of Subject:
Date of Test:
Test No:
Hood Worn:
Putting on the Hood, BA and Helmet
1. How easy or difficult did you find putting on the protective hood over die
BA mask?
No difficulty
Minor difficulty
Major difficulty
2. Did the straps on the BA mask loosen when you put on the protective hood?
Yes
No
3. How easy or difficult did you find putting on the helmet with the
protective hood and BA mask?
No difficulty
Minor difficulty
Major difficulty
Walking on the Treadmill
4. During the exercise were you ever aware that the protective hood moved out of
position?
Yes
5. During the exercise were you ever aware that your helmet moved out of position?
Yes
No
No
Yes
No
7. During the exercise were you aware of any gaps occurring between your protective
hood and the BA mask?
Yes
No
If yes, where did the gaps occur?
8. During the exercise were you aware of the protective hood restricting your
movement?
Yes
No
If yes, where did the restrictions occur?
Yes
No
If yes, please specify what caused the discomfort:
Cool
Warm
Hot
Extremely hot
Cool
Warm
Hot
Extremely hot
Treadmill Exercise Wearing a Gallet Helmet
Name of Subject:
Date of Test:
Test No:
Skirt attached?
Putting on the Helmet and BA Mask
1. How easy or difficult did you find putting on the helmet?
No difficulty
Minor difficulty
Major difficulty
2. How easy or difficult did you find putting on the facemask?
No difficulty
Minor difficulty
Major difficulty
Walking on the Treadmill
3. During the exercise were you ever aware that the helmet moved out of position?
Yes
No
4. During the exercise were you ever aware that the facemask moved out of position?
Yes
No
5. During the exercise were you ever aware of the helmet and facemask restricting your
movements?
If yes, please specify:
Yes
No
-2Walking on the Treadmill
6. During the exercise did any part of the equipment cause you discomfort?
Yes
No
If yes, please specify what caused the discomfort?
Cool
Warm
Hot
Extremely hot
Cool
Warm
Hot
Extremely hot
Thank you for your help
Treadmill Exercise Wearing a Protective Hood and Helmet with a Skirt
Name of Subject:
Date of Test:
Test No:
Protective Hood Worn:
Helmet Skirt Worn:
Putting on the hood, BA and helmet with skirt
1. How easy or difficult did you find putting on the helmet with skirt over
the protective hood and BA?
No difficulty
Minor difficulty
Major difficulty
Walking on the treadmill
2. During the exercise were you ever aware that the protective hood moved out of
position?
Yes
3. During the exercise were you ever aware your helmet and skirt moved out of
position?
Yes
Yes
No
No
No
5. During the exercise were you ever aware of any gaps occurring between your
protective hood and the BA mask?
If yes, where did the gaps occur?
Yes
No
6. During the exercise were you aware of your protective hood or the helmet skirt
restricting your movements?
Yes
No
If yes, please specify what restrictions occurred:
Yes
No
If yes, please specify what caused the discomfort and what the discomfort was:
Cool
Warm
Hot
Extremely hot
Cool
Warm
Hot
Extremely hot
10. If you have any other comments about the flash hood, helmet and skirt you wore during the
exercise, please use the space below:

The Effectiveness And Safety Of Fire Hoods

Transcription

Similar documents

www.afvclub.com - Fort Hood DFMWR

Protective cabin crew smoke hood PBE 15-40F-11

St. Paul Mech Venmar Range Hoods No Logo Apr 12

LITTLE ERIN MERRYWEATHER SYNOPSIS Directed by David

69th ADA Bde - Archived Editions of the Fort Hood Sentinel

RX Top Mount Supercharger V6 Gen 5 Camaro

advanced utility systems

[HOMEL

AcAdemic AppArel bAchelor pAckAge on SAle noW