Material Compatibility of Chlorine Dioxide Gas – Paul Lorcheim

Material Compatibility
Of Chlorine Dioxide Gas
Paul Lorcheim, PE
Director of Operations Decontaminating
the Difficult
Since 2001
Worlds Largest Supplier of Gaseous
Chlorine Dioxide Decontamination
Equipment and Services
1
Revision Date: June 22, 2008
Overview
1. When, Where, Why ?
2. Define Chlorine Dioxide
3. Comparisons (CD vs. others)
4. Define Chlorine Dioxide Sterilization Parameters
5. CSI CD Generation Equipment /Services
6. Exploration of Applications
2
When To Use Chlorine Dioxide Gas
 Renovation
 Between Population / Production Batches
 Commission
 De-Commissioning
 Contamination
 Preventative Maintenance
 …..
3
Where To Use Chlorine Dioxide Gas
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












Procedure / holding rooms
Aseptic / clean rooms
Surgical suites
Pass throughs
Necropsy rooms
BSL-1/2/3/4
Cold rooms
Isolators
BSC’s (A1/A2, B1/B2, Class III)
HEPA Housings / Duct work
Silo’s / Dryers
Buildings / facilities
Processing piping
Processing tanks and vessels
…..
Any enclosed space needing decontamination
4
Why Use Chlorine Dioxide Gas
Safest fumigant available
Fastest cycle times (start to finish)
Most complete Penetration and Distribution
Most Flexible Process
Sterilant process
Easy installation (New or Old facility)
Good Material Compatibility
Both gases (VHP and CD) are effective against biological agents and residual
chemical agents, but destruction of some chemical agents is slow.
Chlorine dioxide was identified as the best available
fumigant for decontaminating parts of the Hart Senate Office Building, as
well as for fumigating mail and packages (1) [Science Nov 2003]
1. J. Patrick Fitch, Ellen Raber, Dennis R. Imbro1, “Technology Challenges in Responding to Biological or 5
Chemical Attacks in the Civilian Sector” SCIENCE VOL 302 #21 NOVEMBER 2003 pp1350-1354.
What is Chlorine Dioxide (CD) ?
Properties:
 Yellow-Green Gas1
 Water Soluble2
 Boiling Point 11oC3
 Tri-atomic Molecule
 Molecular Weight 67.5
1. Ability to be monitored in real time with a photometric device.
Not subject to condensation or affected by temperature gradients.
2. Ability to penetrate water (not all sterilants can penetrate water, vapors
can not)
3. Chlorine dioxide is a “true gas” at room temperatures; which means
excellent distribution and penetration.
6
Chlorine Dioxide Time Line
Aqueous Germicide (Drinking
Water Treatment Longest
User)
1920
Chlorine Dioxide
Recognized as a Gaseous
Chemosterilizing Agent
1984
CSI CD-Cartridge
Registered with
US-EPA
Mar 2004
Time
1811
First Preparation of
Chlorine Dioxide





1940
Bleaching Agent
(Pulp & Paper Industry
Largest User)
1988
First Registered with
the US-EPA for use as
a sterilant
World wide consumption of chlorine dioxide – 4.5 million lbs/day (2.04million kg/day).
743,000 lbs (337,000 kg) released to atmosphere in 2000.
Example: Maine allows 3 lb’s / hour (1.4kg / hour)of CD to be emitted
2004 Ontario reported releases of 114 tonnes (103,419kg)
CD is not listed in the California Air Pollution Control Officers Association Air Toxics "Hot
7
Spots" Program Revised 1992 Risk Assessment Guidelines as having health values
(cancer or non-cancer) for use in risk assessments (CAPCOA, 1993)CD
Types Antimicrobial Pesticides
Sterilizers (Sporicides): Used to destroy or eliminate all forms of microbial
life including fungi, viruses, and all forms of bacteria and their spores.
Spores are considered to be the most difficult form of microorganism to
destroy. Therefore, EPA considers the term Sporicide to be synonymous
with "Sterilizer."
Disinfectants: Used on hard inanimate surfaces and objects to destroy or
irreversibly inactivate infectious fungi and bacteria but NOT necessarily
their spores. Disinfectant products are divided into two major types:
hospital and general use.
Sanitizers: Used to reduce, but not necessarily eliminate, microorganisms
from the inanimate environment to levels considered safe as determined
by public health codes or regulations.
Antiseptics and Germicides: Used to prevent infection and decay by
inhibiting the growth of microorganisms. Because these products are
used in or on living humans or animals, they are considered drugs and
are thus approved and regulated by the Food and Drug Administration
(FDA).
http://www.epa.gov/oppad001/ad_info.htm
8
Decontamination Methods
1. Spray and Wipe / Fogging - Various
2. Ethylene Oxide Gas – Non-oxidizer
3. Vapor Phase Hydrogen Peroxide (VPHP)
– Oxidizer
4. Ozone Gas – Oxidizer
5. Formaldehyde Gas – Non-oxidizer
6. Liquid Chlorine Dioxide – Oxidizer
7. Chlorine Dioxide Gas – Oxidizer
9
Myth of Corrosion
10
Oxidation Potential of Several Biocidal Agents
Oxidation Potential
(volts)
O3 (ozone)
2.07
CH3COOOH (peracetic acid) 1.81
H2O2 (peroxide)
1.78
NaOCl (sodium hypochlorite) 1.49
ClO2 (chlorine dioxide)
0.95
More Corrosive
Biocidal Agent
Oxidation Capacity
(electrons)
2e–
2e–
2e–
2e–
5e–
1
The above table summarizes key properties of oxidizing biocides.
As shown, CD is not as aggressive an oxidizer (oxidation potential data) as
chlorine, ozone, peracetic acid, hydrogen peroxide, or bleach — and it is non
corrosive to common materials of construction.
The fact is that Vapor HP is 1.9 times more corrosive.
1. Wintner, Barry, Contino, Anthony, O’Neill Gary, (2005) Chlorine Dioxide, Part 1 A Versatile, High-Value Sterilant for the
Biopharmaceutical Industry, BioProcess International 3(11)
11
Gaseous CD is not the same as
Liquid CD
 Liquid CD creates the chlorine dioxide through acidification of sodium
chlorite
Common Liquid Generation Methods:
sodium chlorite + water + acid =
Acidified Sodium Chlorite + Chlorous Acid + Chlorine Dioxide
 Liquid CD is corrosive due to acids involved in the generation process
 Gaseous CD is created through a dry gas process
Cl2(g) + 2NaClO2(s)
yields
2ClO2(g) + 2NaCl(s)
 Only pure gas is delivered to the chamber, the salt solid remains in
the CD Cartridge
12
CD does NOT form Hydrochloric Acid
 ClO2 dissolves in water
 ClO2 is water soluble
Water Droplets:
 ClO2 does NOT dissociate in water
 ClO2 does NOT hydrolyze in water
After 5 runs each at
5mg/L for 7 hours
88 equivalent runs
 ClO2 does NOT react with water
 ClO2 does NOT NOT NOT form hydrochloric acid
 Salt dissociates in water
 NaCl(s) --> Na+(aq) + Cl-(aq)
 Chlorine forms hydrochloric acid
 Cl2 + H2O --> HCl + HOCl
13
Outside Testing
14
Material Compatibility
EPA Comparison of Decon Agents
Snyder, Emily, “Indoor and Outdoor Decontamination” Presentation at EPA Region 9 / ORD
Homeland Security Research Workshop, July 14, 2011 San Francisco, CA. Accessed from
http://www.epa.gov/osp/presentations/homesec11/hs_Snyder1.pdf . Accessed on 1-10-2013
15
Purdue Study (Materials of Construction)
•
•
•
•
Chlorine Dioxide Chamber
– 304 stainless
– ~75 ft3
– Fruits and Vegetables
Materials Compatibility
– Aseptic Materials
– HVAC materials
– Electronics
Emulate Aseptic Bio-Decon
– 2mg / Liter
– 6 hours
Extended testing
– Materials left at Purdue
16
Materials Compatibility Study
17
Conclusions of Purdue Materials Study
•
•
•
•
Metals
– No oxidation observed
– 316L, 304, Copper, anodized Al,
Novel metals
Polymers
– No oxidation observed
– PVC, Lexan, Epoxy, PP, Phenolic,
Urethane binders
– Siloxane gels absorbed/desorbed
Electronics
– No oxidation observed
– Contacts intact
Incompatible with
– Urethane foam
– Clear flexible urethanes
18
HEPA Filter Manufacturing and Use
•
Not manufactured in GMP facility
– Warehouse environment
– Some aspects conducted outside
•
Limited data suggests new HEPA
filters will grow
•
HEPA filters cannot be heat sterilized
•
Filter media damaged by mechanical
cleaning
•
Not sterile when installed
19
HEPA Filter Study at Purdue University
•
•
•
•
•
Remediation Study
• 10 mg/L, 95% RH, 2 hours
• 5 mg/L 95% RH, 2 hours
• BI Geobacillus stearothermophilus.
• BIs inserted 6 inches into pleat
• No air circulated through filter
Analysis
– BIs neutralized w/ Sodium Thiosulfate
– Incubated in TSB at 58 C for 7days
Results
– No BI growth
Data shared with HEPA Mfgs
– Interest in supplying sterilized filters
No degradation to filter, glue, or seals
with CD
20
Contract Sterilization Examples
 Contract Sterilization is the process where ClorDiSys can
decontaminate / sterilize your items, equipment, supplies, and
products at our facility and then ship them back to you (or
someone else).
 It can be returned under sterile conditions or just decontaminated.
 ClorDiSys uses chlorine dioxide gas for sterilization of
components instead of gamma irradiation, ethylene oxide gas, or
electron beam methods.
21
Example: Items in Isolator Chamber
22
Example: Items in Isolator Chamber
23
Example: Medical Device Components
24
Example: Printers and computers
25
Example: Electronic Product
26
Material Compatibility
Formaldehyde
VPHP
CD
Electronics
Very Good1
Good2
Good2
Equipment
Very Good1
Good2
Good2
Wall Paint
Good3
Good4 Condensation
bubbles paint
Good4
Floor Paint
Good3
Good4 Condensation
bubbles paint
Good4
Ductwork (Galvanized)
Very Good1
?5
Good2
Ductwork (SS)
Very Good1
Good2
Good2
1.
Formaldehyde can leave residues without actually causing material damage
2.
All are oxidizers which have the potential to cause oxidation
3.
Formaldehyde can leave residues and leave brown stains
4.
Potential slight yellowing of urethane based paints
5.
Galvanized metal breaks down VPHP
27
Safe On Materials!
 Chlorine dioxide gas is safe on most materials, including stainless
steel, anodized aluminum, painted steel, plastics, gasket materials,
and electronics.
 Material testing is available for new items / materials
28
What is the Process?
29
The Chlorine Dioxide
Decontamination Process
 Pre-Conditioning
Chamber Leak Test and Raise RH 65%-75%
 Conditioning
Dwell time at RH SP
 Charge
Raise CD Concentration 1 - 5 mg/L
 Exposure
Dwell time at CD SP
 Aeration
Remove CD Gas 12-15 air exchanges
30
Example Applications:
31
Example Application:
32
65 Room (180,000 ft3 – 5097 m3) New Animal Facility
Initial Decontamination Service
10 Injection Locations
7
20 Sensor Locations
3
4
4
2
6
8
10
5
8
1
9
20
18
6
5
9
16
15
10
19
3
12
14
2
17
1
7
13
11
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65 Room New Animal Facility
Chemistry Labs
34
65 Room New Animal Facility
Changing Stations and BSC’s
35
65 Room New Animal Facility
Storage Rooms
36
65 Room New Animal Facility
Animal Holding Rooms
37
Sterilization of Juice Storage Tank with Piping
38
Sterilization of intermodal transportation
containers
39
Spiral Freezers
“We swab
intensely every
weekend and we
have been totally
clean! This has
definitely been a
success “
40
Spiral Freezer
 Positive swabs for Listeria spp.
 Decontaminated a ~25,000 ft3 spiral freezer with CD gas (720 ppm-hrs)
 Continual swabbing 2-3 times/day for 6 weeks after treatment
without Listeria spp.
Decontamination Area Photo
High Ceilings (90ft - 27.4m)
42
Decontamination Area Photo
High Ceilings (90ft - 27.4m)
43
.
Decontamination Area Photo
High Ceilings (90ft - 27.4m)
44
.
High Ceilings (100ft –
30.5m)
45
Component Load Transfer Isolator (25 ft3)
Total 31 ft3 (0.9m3) with docking station
Total
Decontamination
Cycle Time - 1
hour 20 minutes
Example of
Good
Penetration
Ability
There were a total
of 25 biological
indicators (Bacillus
subtilis) placed
throughout the
chamber and load
with NO positives.
46
Train of Isolators (279 ft3 - 7.9m3)
CD Gas
Injection
Workstation
Isolator
Autoclave
Interface
Autoclave
Isolator
Example of Good
Distribution Ability
There were a total of 24 biological
indicators (Bacillus subtilis) placed
throughout the chamber and load with
NO positives.
Workstation Isolator / Autoclave
Interface Isolator and Autoclave (Total
Decontamination Cycle Time - 1 hour
52 minutes)
Mix-fill, measuring and packaging process Isolators
Lyophilizers (Freeze Dryers)
3 hour cycle
CD cycle run every 2 weeks
Old steam cycle 24 hours
with heat up /cool down time
Filling Line Isolator (250 ft3 - 7m3)
Amgen
Thousand Oaks, CA
50
Microbial Challenge Room (6000 ft3 - 170m3)
Example of Good
Material
Compatibility
51
Decontamination Chambers
52
IVC Rodent Racks
53
Portable Decontamination Chamber
54
Transport / Delivery Vehicles
55
BI Location Inside Open and Closed Cabinets
Both BI’s Killed
Example of EXCELLENT
Penetration Ability
BI Placed in OPEN Cabinet
56
BI Placed in CLOSED Cabinet
BI Location Under Equipment
Example of EXCELLENT
Penetration Ability
Both BI’s Killed
BI Placed UNDER Equipment
57
BI Location Under Equipment
Example of EXCELLENT
Penetration Ability
BI Placed UNDER Equipment
58
BI Location Between Components
Example of EXCELLENT
Penetration Ability
Both BI’s Killed
BI Placed Between Components
59
BI Location In Cage In Ventilated Rack
Both BI’s Killed
Photos
60
HEPA Housing
61
BSL-3 Suite
62
Sterilizing Filters (mounted incorrectly)
63
Equipment Decontamination
64
Necropsy Rooms
65
Surgical Suite (2000 ft3 - 56.6m3)
Example of Good
Material
Compatibility
66
Passthrough Rooms
67
Passthrough Rooms (325 ft3 - 9.2 m3)
2.5 hr cycle time
68
Pass Through Room
(864 ft3 - 24.5m3)
Example of Good
Penetration
Ability
69
Lumen Sterilizer Load (Total Sterilization
Cycle Time - 3 hour 40 minutes)
Example of Good
Penetration
Ability
70
Aseptic Juice Filling Room
115 sq m (20,000 ft3 – 566.3 m3)
71
Pharmaceutical
Aseptic Filling
Suite
15,000 ft3 (424m3)
Location: Major
Pharmaceutical
Manufacturer in
Korea 72
Pharmaceutical Chemistry Lab
160 sq m (17,000 ft3 - 481 m3)
73
Process Tanks and Piping
Example of Long
Distances True
Gases Can Travel
74
Building (167,000 ft3 - 4730m3)
University of Pennsylvania
Bolton Center
Kennett Square, PA
75
Various Equipment
76
Automated Guided Vehicle (AGV)
77
Control Room with computers & Equipment
78
Transmission Cryo-Electron
Microscope (JEOL Cryo-TEM) $3,000,000
“Our early attempts to use VHP with JEOL
microscopes were not successful because of
unacceptable level of corrosion …
…We therefore selected ClO2 (CD) for the
microscope decontamination.“
Minidox – M
Gaseous Chlorine Dioxide
Decontamination Machine
Sherman, Michael B., Trujillo, Juan, Leahy, Ian, Razmus, Dennis, DeHate, Robert, Lorcheim, Paul,
Czarneski, Mark A., Zimmerman, Domenica, Je T’Aime M. Newton, Haddow, Andrew D. and Weaver, Scott
C., “Construction and organization of a BSL-3 cryo-electron microscopy laboratory
at UTMB”, Journal of Structural Biology 181 (2013) 223–233.
Various Equipment
80
Various Equipment
81
Various Equipment
82
Various Equipment
83
Various Equipment
84
Various Equipment
85
Workstation Isolator (350 ft3 - 10m3)
86
Flexible Isolators (25-30 ft3 - 0.7-0.8m3)
87
Rigid Isolator (100 ft3 - 2.8m3)
88
Summary
Safest fumigant available (odor detection, low concentration
levels, non-carcinogen)
Fastest cycle times (start to finish)
Most complete Penetration and Distribution
Most Flexible Process (rooms, BSC’s, HEPA Housing, Duct
work, isolators, suite of rooms, etc)
EPA Approved Sterilant process
NSF Approved process
Compatible with materials typically found in a Research or
Production Facility
89
Compatible with Fresh Strawberries too!
Untreated and stored for 6
weeks at 4oC
Treated with 10 mg/l Chlorine
dioxide gas for 10 min and
stored for 6 weeks at 4oC
Han Y., Linton, R.H., and Nelson, P.E., Inactivation of Escherichia coli O157: H7 and Listeria
90
monocytogenes on strawberry by chlorine dioxide gas, annual meeting of Institute of Food Technologists,
Anaheim, CA, 2002.
Prepared by:
Paul Lorcheim, PE
Director of Operations
ClorDiSys Solutions, Inc
www.clordisys.com
PO Box 549
Lebanon, NJ 08833
Phone: 908-236-4100
Fax: 908-236-2222
E-mail: paullorcheim@clordisys.com
Decontaminating the Difficult
Since 2001
91
• All the treatments were for 10 min at 20oC.
Aqueous and Gaseous ClO2 vs. Washing for
Reducing L. monocytogenes on Peppers
9
Log Reductions
8
Aa
Uninjured Surface
7
Injured Surface
6
5
Bx
Ab
4
3
2
By
1
Ac
By
0
3 mg/l ClO2 Gas
Treatment at 90% RH
3 mg/l ClO2
Solution Treatment
Water
Washing
(Han, Y. et al, Reduction of Listeria monocytogenes on Green Peppers (Capsicum annuum L.) by92
Gaseous
o
and Aqueoous Chlorine Dioxide and Water Washing and Its Growth at 7 C, Journal of Food Protection, Vol
64, No 11, 2001 pages 1730-1738)
What is an Effective
Decontamination?
 All Decontamination methods can work based
on the following:
 Must reach ALL surfaces for a prescribed
amount of time, which means you must
have:
1. Good and Complete Distribution
2. Thorough and Total Penetration
3. Sufficient Contact Time
4. At specified concentration
 Any decontamination method requires a
complete and thorough distribution of the
sterilant or high level liquid disinfectant to get
an effective decontamination
93
CD is the Safest Fumigant
CD
VPHP / IHP
Formaldehyde
Ozone
(time weighted average)
0.1 ppm ☹
1.0 ppm ☹
0.5ppm EU
0.75 ppm ☹
0.1ppm ☹
Typical Concentrations
360 ppm ☺
750 ppm ☹
8000 ppm ☹
20-1000ppm ☺
NO ☹
YES ☺
NO ☹
3-4 hours ☺
6-12 hours ☹
12+ hours ☹
6-72 hours ☺
NO - ACGIH ☺
NO - OSHA☺
YES – ACGIH ☹
NO – OSHA ☺
YES ☹
No ☺
YES ☺
YES ☺
NO ☹
Yes ☺
Penetration &
Distribution
YES (gas) ☺
NO (Vapor) ☹
YES (gas) ☺
Yes (gas) ☺
Penetrate Water
YES (gas) ☺
NO (Vapor) ☹
YES (gas) ☺
Yes ☺
Outside room☺
Bioquell Inside ☹ /
Steris Outside room
Inside Room ☹
Inside and Outside
Room ☺
30-60 min☺
overnight ☹
1 hour + cleanup
30-6094
min ☺
OSHA 8 hr TWA
Odor Detection
Cycle Times
(Risk of Exposure)
Carcinogen
Vented to Environment
Equipment Location
Aeration Time
CD is the fastest to the
TWA 8hr threshold
YES ☺
At 8 hour safety level
☺
☹