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The Nationa-l Fire Protection Associrtion owes its origin to the fire sprinkler
and, more specifically, to the desfueof folward-looking insurers to stardaxdize sprinkler design ard installation. Ftom this desire, NFPASgreater hre protection mission
grew.
The history of the sprinkler-and, in fact, of all automatic suppressionsystemsbegan 173 yeaxsbefore the founding of the NFPA in 1896.Patented in Englard by
Ambrose Godfrey, the first fire sprinHer system consjsted of suspendedcasks of
water to which chambersof gunpowder were attached.A rising fire \ /ould light fuses
stretched between the casks, the gunpowder would blow apart the casks, and, with
a hope and a prayer, the shower of water wor d put out the fire.
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The first true sprinkler
system to be installed in
North America was a
perforated pipe system,
instaled in a New England factory in 1852.Perforated pipe systems were
eventually installed in other
mills and factories, but they
weren't the truly automatic suppression
devices we know today. Though wellintentioned, pedorated pipes weren't
much of ar improvement over Godfreys
exploding water baxlels.
Modern sprinkler technolosr made its
debut in 1874,when Henry Parmelee was
awarded t}le filst U.S patent for an automatic sprinkler system. With its valve head
held closed by a spring of fusible materia.l,
Paxmalee's new sprinkler was the fiIst
pmctical automatic spinlder inventedfor a
wet-pipe system. Parmelee'ssprinklers
were inst lled ertensively thrcughout New
England in subsequentyears.
New England's cold weather also led to
l,hedevelopmenlof l,hefirstdry-pipesprinkler system.Early attemplsro keepsprinklers from freezing mainly consisted of
adding antifreeze solutions to the regulax
wet-pipe systems. This was followed by
the development of a mechanically operated valve that held water back from the
sprinkler supply piping until the fusible
cord keepingt}le valve closedwas meltedby
the heat of a fire. At this point, waler would
rush into the system to douse the flames.
One such dry-Pipe valve, the bellows
differential dry valve, was patented in 1885
by Ftederick Grinnell, the narnesakeof the
Grinnell Corporation. This design, which
used air pressure to hold water below the
clapper, was the forerunner of the dly-pipe
r"lves in use today.
Another spinlder pioneer lTas Charles
Potter. founder of Potter Electric Signal
Compar.ryin 1898.Pottet who was active
in the NFPA, designedhis own water flow
alarm and sprinkler supervisory systems,
which initiated ar alrrm when water pressure in the system decreased.
The speed with which
sprinklers caught on
commercially led to severa.l different insurance
company stardards a.nd
manufacturer designs for
sprinkler systemsby the late 19th century.
As many as 86 different tjrFes of automatic sprinkler hea.dswere marufactured by
more than 40 different manufacturerc
between 1878altd the early 1900s!
With the many different sprinldels came
mary different installation methods arld
starda-rds,however It soon becane obvious to those representing fire insuralce
ard sprinkler manufacturing interests that
this "plumber's nightmare" had to be
solved. So a group representing industrial
underwdters and inswers, sprinkler compalies, and inspection bureaus set out rn
1895to create unifom sprinkler nrles
Hosted by E. U. CrosbY of the Underwriters Bureau of New England, attendees
included ljbefto C. Crosby, chaitman of
the Factory Improvement Committee of
the New Englard Insurance Exchange; W
H. Stratton of the Factory Insurance Association; John R. Fleemarl of the Factory
Mutual Fire Insurance Companies;FYederick Grinnell of the Providence Steam ard
Gas Pipe Compary; and E Eliot Cabot of
the Boston Boaxdof Fire UnderwdteF. No
record of that meeting exists, but it
appears from subsequent events that the
insurance company representanves pre_
sent were impressed with what Mr. Grinnell, a sprinller pioneer, had to say about
sprinkler performance. They were also
impressedby the successthe Factory Mutuals e4joyedunderwdting sprinldered build-
A long woy
from lhe
Pnrrnolee
sprinkle4
lhis one
incorporoles qettheti.c .ts
well qs
funclionoliiy irlo its
design.
ings u'ith more consistent sprinkler insta-lla
tion mles.
Cooperation and consensus finally led to
the founding of the National Fire Protection
Association and the first Standard for the
Instaliation of Sprinlder Systems in 1896.
The firct ha.lf of the 20th century saw the
development of different fusible links that
increased sprinkler response speed and of
a number of other technological advances
that made sprinklers more reliable.
In 1955,as a result of extensive research
at Factory Mutual, the spray sprinkler
deflector was modified to provide a more
finely dispersed and more unitbrm downward pattem. These new spdnklers
became known as the sta.nda-rdsprinkleN,
'oldand the older models becarne the
style' spdnklers.
Water danuge has always been an issue
with sprinklers, and to mjnimize it, the
cycling va.lve was developed in 1967, and
the on-offspdnkler was developed in 1972.
According to Mike Bosma of Viking Cor
poration, cycling valves allow the riser of a
preaction system to turn itself off after a
protected area has cooled down, but
allows the system to tum or agaill should
the fire reignite, lhereby providiig eiTerc
tive protection while limiting water dischaxge.
AJso developed were the single ard double interlock systems. The double lock system prevents accidental water discharge
by requiing that a detector operate and a
sp nkler actuate before any water actua-lly
ente6 the s),stem piping. Double interlock
systems are used in a-reashighiy sensitive
to water dainage, such as freezeN ard
computer rooms. The single interlock system, also kiown as the superwised preaction system, is used in axeas sensitive to
water damage, too, but it has one lock
instead of two. Water llows into the system
piping after ar electrical or pneumatic
device is tdggered, and water flows onto
the flle after the spdnkler opens. This pro*
vides protection from false operation,
while maintaining the speed of water applicar;onepenence in ! pt pjpe syslem".
These two tlpes of sprinkler systems
axe simila.r.In the single interlock system,
however, water flows into the piping aftef
only one actuation-that is, detection. The
double interiock system requircs both ;rn
open sprinkler ard a detectorbefore water
can enter the system.
Continlrcd on page 38
SPRIilKLERS AND ALARTi SYSTEI,IS
!:=
Sprinkler systems axe not only frre
suppression systems,they axealso fire
detection systems. The fusible linl<s
ard explosive liquid-filled bulbs act as
precise mini fire deteciors. The waterflow is the indication of fire, ard a
waterllow switch can initiate a sprinkler alarm signa]. Therefore, a waterflow switch is one of the important
pieces of all the initiating devices of an
alaxm system in addition to matrual
ala-rm boxes, as well as heat, smoke,
and fire detectors.
"Sprinlder systems axe fairly
simple
and stable systems," remarks Joe
Ttigg, Jr, of Potter Electric Signal Co.
Yet, as integal components of a com,
plete fire protection plarL monitoring
of thet activity is essential,not only to
ensu.rethe proper functioning of a system when inactive, but to 'notify ownels, central stations, and fire departments" when activated, to minimize
water darnage after the fire has been
suppressed.
As such, sprinlder systems must be
monitored by a stuucture's hre alarm
ard detection sJrstem.Companiessuch
as Potter have developed ways to integrate sprinklers into the complete
supervisory ard active roles of fire
alarm systems. In addition to waterflow, the fire alaxm system should
monitor the normal, udnitiated conditions of a sprinkler system. Supervisory switches such as pressure,gate, or
post indicator valves indicate to the
alaxm system if a system control valve
has been closed, or if the system has
been otherrvise impaircd, indicating a
"supervisory off-normal condition."
Likewise, when system conditions axe
returned to norma.l, the fire alarm
control system must indicate a
'supervisory restoration
to normal
signal."
Tfigg explains that, just as ala.Im
ard detection systems suffer from
fa.lse a-laxms,sprinklers car be affected by llows ard surges that can trigger
alaxms. Vare-type monitors, such as
those offered by Potter, include a
retard mechanism to reduce the nunrber of false alarms.
BRINGING IT ALL BACK HOIhE:
TIIE DEVETOP'hENT OF RESIDENTIAL SPRINKTERS
4
The concept ofthe residentia-lsprinkler
up ro lethal lavpls. To kepp rhis from
is more thar 50 years old and has had
happening, fires had to be suppressed
mary advocates over time. In fact, the
earlicr, bpforp pcriculalcs and fLUnes
first residential sprinkler ordinance
could rise to dargerous levels.
was passed in 1969 in San Clemente,
Through these and other tests, marCalifornia. But the concept of a sprinufacture$ developed a new quickkler made for the unique conditions of
r e s p o n s c r p s i d c nr j a l s p r i n l d e r l h a r
dwelling fires didn't become a reality
could supprcs- fire in jts incipienr
until 1976, v,'hen the U.S. Fire Adminis
stages. l-i6t released in November
tration began promoting research into
1980, NFPA 13D, Stand.&rd. on Sprinresidential sprinkle.Is.
klpt Sljstrtu9 in Otp- oruJ Tuo-Fom;t"
At the time, tests run by the Factory
Dueuings and, Menufaatured, Eomes,
Mutual Research Corporation revea-led required thal only quick response resi
thal a sundard sprinkler was nol scnbi
dential sprinklers be used in one- and
tive enough to ensure the life safeff of
lwo family duel)ings a.nd mobil.
homes.
occupants of dwellings. Although a
standard sprinkler could protect propSprinl<lerIechnolog is finally bringertj/ and preserve the integrity of a ing fire protection to the front line of
structue, it allowed caxbon monoxide
the war: on flre-the Amedcan home.
and eye level gas tempemtures to build
Con LbLued.Jhtn page 35
The 1970ssaw a much nore rapid development in sprinkler technology, when
rcsea-rch on fir-st-response sp nklels bcgan.
A s C e r u i dR . S , h u l t zo l S ,h r r r r ' E r r g i n , r.
ing obser"v'es,much of the change in sprin
kler technolosr "is the rcsult of research
"
done for fast'response sprin lders.
Thl. con.pp ol the lJ5t.rp\po sl. :frilkier \4'as frst brcached in relation to arl
occupancy in l\'lri(i sprinklels were not tra
(iiliona-]lyilsl.alled: tlxr ilorne- After all, tnost
lD'esin the Lhitcd Sl.al.esoc.ur-ir the honre.
The la-stresponse sprinklel provide(i,
for the filst time, a high degree of protec
tion lbr those caught in the roon of frre
o gin by keeping lcthal products ol cotn
bLrstion, which kill nore people than
flrlrr1es,rvilhin tenable limits. This allorvs
r J r u : ,, J U h r i n a f i r e a g r e a r " rL , p p o f l u n i
ty to evacuate safely.
Residential qrrinldcr testing a.lsoinitiatecl
o l l r e r i r | | D r o v p m p n r ,\ , ' p r i | | L l e r r l e - . t n .
inchrding larger odlices and rnodified
deflectors, both of wliicli permil a larger
'fhe
area of c1x'erage.
e\tra lalge orilicr' C:rn
Iilewatsr-mhtsystem
eftin[uhfies
firm[ytafiing
leat
away
from
t|ie
llamcs
anil
ilampeniilg
l|trsuilffie
oladditimalfuels,
also help exiend coveragein areasin which
According to lt4ilke, the goveming prinwaJerpressureis low.
ciple of the misting system is early fire
The 1970sa.lsosaw the debut of laxse- suppression by reducing heat and preventdrop sprinklers. first developed by the ing other materia.ls neax the fire souce
\tking Corporation to deal with high-chal from igniting.
"The water-mist
lenge fires in waxehousesby improving
system extinguishes
water delivery though the fire plume to fues by taking heat away lrom the flarnes
the seat of a fue. The laxge-dropsprinkler ard dampening the surface of additiona.l
was the fiIst extuaiaxge-orificetJpe sprin- fuels,' Milke says.Oxygen djsplacementis
kler designedfor storage applications.
faidy low and has a negligible effect on the
Also developed in the 1970s was the actual extinguishment. "Because these
concea.ledsprinkler ConcealedsprinkleB, fires axe caught by the mist systems in
such as the Stax Unspoiler introduced by their incipient st€ges, they don't create
Star: Sprinlder in 1971, quickly became enough steam for a displacementeffect.'
popular in the axchitectual community
The water-mist system'seaxlyacti\,?tion
due to their aesthetic !due. Like other Urough incipient detection, coupled with
sprinklers, concealed sprinklers have low-flow chaxacteristics, presents a cleax
evolved to suit specific applications, adva-ntage for librades, museurns, and
including quick response,residential, ard offices where large volumes of water
clean room vaxieties.
could damage priceless collections or
In the eaxly1980s,nanufactuers such as expensivecomputer systems.Grilmell and
St€x Sprinlder also developedthe tamper- several other compar es axeexploring the
resistant sprinkler for use in instituuonal application of water mist in atucraft,ships,
settings such as penitentiaxiesand mental and telecommunications.
hea-lth facilities. Several marufactureN
Grinnell recently received a LrL listing
now maxkettarnper-resistartsprinlders.
for use of stainless steel, open, AMl0 nozOther recent advarces in sprinkler tech- zles as a component of a pre-engineered
noloS/ have to do with components and water-mtst system, according to Walne
accessories,including the development of Maxcotte of Grinnel. In testing, the nozfue pump systems,such as horizontal split- zles effectively extingujshed a \,?xiety of
case models, prepacka€ed s,6tems, and exposed and shielded Class B hydrocarvertical in-line pumps. Products offered by bon pool, spray, and cascadingpool fues,
Patterson Fire Pumps axea good example. as well as combination-sof incidental Class
The companysPre Pac,for instance,is a A and ClassB fires, says Maxcotte.
prepackaged,split-case pump that is selfThe NFPA anticipated i-hedevelopment
contained,and, therefore, provides reliable and implementation of water-mist systems
fire conkol while il rcduces labor, engi- ard is currently working on a new stanneering,and insta.llationtime.
daxd to help guide the proper use of this
Prepackaged systems have become new technolosr. As sprinklers have been
especially prevelant in preaction systems. refined for more and more specific appliThe complexity of the equipment and the cations, so too rMillwater mist. I
qua.lity of the electrical connections has
led to a boom in preassembledpreaction
syslenrs.Suchsystcmsinrlude all the pre- Sorncm
acl-ion equipment required at the riser, Coleman,Ronny J., Alpha to Omeg&,Phoe tx
including the releasepanel, air supply, and Publications, San Clemente,Califomia, 1985.
all comections.
C,oIematr,
RD V J.,R8tdenJinl Wnlcler SAstems:
The newest sprirlders axen'ttechnically I'ntectting Life atu1Ptltpary, Nation l Fire Pmsprinklers at all-they're water-mist sys- tection Association,Quincy Massachusetts,1991.
lems.For |Jlepast few years,the Universi Grcer, Mlliarn, fl?,etliistary oJAklrm SecuritA,
ty of Maxylard's Fire and RescueInstitute National Burglar & Fire Ala.rmAssociation,
(MFRI) has been experimenting with Bethesda,Ma.rylard, 1971.
water-mist systems, a-nd their tests are Miller, Felicia, "FtueSprinkle$ Equal Fire Safeproving that water mist successfully sup- ty," Va,lueMagd,zine,Fdl1990, pp. f9-22.
presses{ires in the beginning stages.
Schirmer, Chester W, "Spdnklers: A Chalenge
"The intent is to operate quicldy
ard do for the F\ture," Ilrc ./ounnL May 1986,p. 116.
as little water damage as pocsible," says Schultz, Gerald R., "Keeping Up with the Lalest
Dr. JamesMilke, assistantprofessor of fire in Sprinkler Tbclmology," NFPAJournal,
protection engineeringat the Univelsity of May/June1994,pp.3&42.
Maryland. "The recent interest in warer Solomon,RobertE., PE., ed.,Autamatltc
mist came about as a result of the prohibi- Sprinklcr Hatulbook, Si\1h Edition, National
tion of halon and the rrater mist system's Firc Protection Association, Quincy, Massachuvery lorMflow capabilities."
setts,1994.