13. CHAPTER - 13 Fire and Explosion

8/19/2019 13. CHAPTER - 13 Fire and Explosion

1/40

CHAPTER - 13

Fire and Explosion

1. General :1.1 Nature of Fire1.2 Need of Fire Safety 1.3 Factors or Causes contributing

to Fire2. Fire and Explosion Peno!ena :

2.1 "e#nitions2.2 Ce!istry of Fire2.3 Stages and Spread of #re2.$ Fire %oad2.& Explosion2.' "e(agration and "etonation2.) Con#ned and *ncon#ned

+apour Cloud Explosion ,+CE-2. /%E+E

3. Classi#cation of Fire andExtinguisers

$. Statutory and oter Standards :$.1 Statutory Pro0isions$.2 ndian Standards$.3 Guidelines of egional ari4

5d0isory Co!!ittee ,5C-$.$ NFP5 Code ,NFC-

&. "esign for Fire Safety:

&.1 Fire esistance of /uilding6aterials

&.2 Fire Safety of /uilding7 Plant7 Exit7E8uip!ent etc.

'. Fire Pre0ention and Protection Syste!s:'.1 General Control 6easures'.2 Fire "etection and 5lar! Syste!s'.3 Fire Suppression or Extinguising

Syste!s:'.3.1 Portable Fire Extinguisers'.3.2 Fixed Fire nstallations:

9ydrants7 Sprinlers7 ;aterspray7 Carbon dioxide7

Foa!7 "CP and otersyste!s

'.3.3 5uto!atic Fire "etection <Extinguising Syste!

'.$ Control of Fire and Explosion inFla!!able Substances

'.& Figting Fires of Pesticides'.' Electrical Fires'.) E4ects of Co!bustion Products'. Fire E!ergency 5ction Plan < "rill

). nspection7 6aintenance and raining

1 GENERAL

1.1 Nature of Fire :

Fire is an igneous element whosepotentiality is well recognised in ourIndian culture. Like Âý· æàæ (light)!æ"# (wind) and $% (water) &' (*re)is our +od and we worship them toprotect us. ,hey are the supremeelements and without them the humanli-e is not possile. !/#æ0 Âæ!· pæ'1and &21' is said y Lord 3rushna inGita meaning therey that he is &'amongst eight +asus. "4æ is the di5ine-orm o- &' and through "4æ weachie5e e5erything.

,he destructi5e nature o- *re andneed o- protection is also e6plained as

-ollows7

8 9æà:;pæ'à:;<àæ=æ#à:;>?@A! BC

Â#< Â#< Âý!DE?GH ?>1æ?à:;0 à:;"G? CC

Jemainder o- det *re and enemygrows again and again there-ore theyshould e ended not lea5ing any

remainder. It is e6plained earlier that ·KÂM "# N?0 ÂýOPQ?H !'Ræ ST2H i.e. it is o- no use to dig well when it isalready *red in the home. us

pre0ention is better tan cure and it istruer in case of #re pre0ention.

1. Need of Fire !afet":

Uain oVect o- *re sa-ety is to protectli-e *rst and property ne6t -rom the

ra5ages o- *re. WVecti5es o- *re sa-etydesign are sa-ety o- li-e protection o-

1

THEME


2/40

property and continuity o- operations. Firesa-ety planning is reXuired -or sites aswell as uildings. In industry it is reXuired-or workers and pulic.

Yotentiality o- *re is tremendous as itholds the largest range o- damagingcapacity -rom a small urn to the

disastrous damage o- plants persons andproperties. >ome glorying e6amples o- *re and e6plosion are gi5en in ,ale Z[.Z.

Ta#le 13.1 \6amples o- UaVor Fire $ea

rPlant % Pla&e 'eat

(!eriou

s)n*urie

s

Z]^_

òal duste6plosion `hina

Zb_

Z]^^ >hip e6plosionomay _[Z ^bZ]^b

>hip*refe6plosion

,e6as >

b _

Z]

,ruck e6plosionòlumia

ZZ

Z]b

Uine e6plosion`hasnala India

^[Z

Z]j[

Fire in Jailwagon ihar

] [

Z]j^

Yetrol line *rerail

Z]j^

LY+ *re Ue6ico b

Z]j

Yetrol roadtanker3arnataka

[] j

Z]][

Fire in a toy-actory

,hailand

_ZZ

Fire in a plastictoy -actory

`hina

j^

Z]]^

uge *re in oilre*nery àiro\gypt

Z[_

Fire in a dancehall eiVing`hina

_[[ Z

Z]]

Fire in a mo5ingtrain UoscowJussia

[b

Fire due to short

circuit >irsaariyana

[j

leaking gaspipelinee6ploded

,aegu >outh3orea

Z] Z

Z]]

isco *reUania

Yhilippines

Yetroleumpipelinee6plodedeiVing `hina

^ b

\6plosion in a*re works-actory>i5akasi ,..

Z^ Z

Z]]b

Fire in areligious

con5entionhuaneshwarWrissa

_ b

Fire in *recrackers shopeiVing `hina

__ _

Fire in shipreaking yardlang +uVarat

Z^ Z

+as *re inpilgrims tentsUecca >audiraia

[^[

Fire in a pandalnear temple

,hanVa5ar ,..

_

In a sudden rushdue to *re qe6plosion at aswitchoard in agarment-actory hakaangladesh

_^ Z

Fire -ollowinge6plosion in are*neryishakhapatnam Y

Z]]j

òllisionetween an oiltanker q ^5ehiclesIslamaadYakistan

Fire whilemopping up

2


3/40

petrol spillage-rom a urstpipeline in>outhernigeria \gypt

\6plosion o- aleaking LY+

tanker in aparking lot at3hanapara+uwahatissam

ZZ Z

òllision o- aus with an oiltanker

agdishpurihar

[

Z]]

]

+as e6plosion in

a coal mineeiVing `hina

[ j

_

Fire at`hristmas party(discotheXue) inlXoyang city in`hina on _Z__.

[]

Courtesy 7 LY ews.

>imilarly some e6amples o- estimated *re loss in-erred -rom the *re

insurance claims are gi5en in ,ale Z[._.

Ta#le 13. Exa+ples of ,re loss

'ate Pla&e Loss inCrore of

Rs.

j_ àlico Uillsaroda

Z.Z

[]^ Yarasrampuria >ynthetics

Z[.[_

Z_]^ ,ata

`hemicals

Z.

ZjZZ] UadrasJe*neries

Z.

Z^Z_] ikram Ispat _.ZjZZ] Fire on goods

train in ,unnelFrance

[ >

Z^]]b Fire at Y`Lre*neryiag Y

Courtesy 7 LY ews.

,hese roaring *gures o- hea5y losseso- men and money strengthen thepermanent need o- *re sa-ety. In industrywe store and use many materials whichare capale o- gi5ing or catching *re.Uany processes eXuipment andsituations create *re haards. ll these

need proper detection and measures o- *re pre5ention and control. ,his is in theinterest o- all.

1.3 Fa&tors or CausesContri#utin to Fire:

Figures -or > -rom ccident FactsZ]]b are reproduced elow 7

Causes of 'eat(s

due to Fire %Fla+es

Nu+#er of

Fatalities1

1

31

/

ònvagration(widespreaddestructi5e *re)

[^b [[j^ [^b

Ignition o- clothing Z_ Zb ZIgnition o- highlyinvammale

b ^_ ^

Wther unspeci*edmaterial causes

_b^ [Zb [Z

,otal []j [] []j

Fa&tors &ontri#utin ,re:Wne study o- more than Z] *res in

industrial plants re5ealed the -ollowing-actors contriuting to *re7

Fa&tors 0

\lectrical Z]Foreign sustance Z_>moking q matches j

ot sur-aces bW5erhead materials [Uiscellaneous Friction Z^Wpen vames ]>pontaneous ignition jòmustion sparks >tatic electricity _ot determinale b

,otal Z

Co++on Causes of )ndustrial Fires:

3


4/40

nother study o- more than _*res reported to the Factory Uutual\ngineering òrporation -rom Z]j toZ]bb gi5es -ollowing causes7

Causes of ,re 0 !(are

\lectrical __

Incendiaries (delierate*re) Z

>moking ]ot sur-aces ]Friction bW5erheated materials bùtting q xelding burner vames >pontaneous ignition \6posure ^òmustion sparks [Uiscellaneous [Uechanical sparks _Uolten sustances _>tatic sparks _`hemical action ZLightening Z

,otal Zo5e percentage indicates the

-reXuency o- *re causes. It is notindicati5e o- their relati5e importance atparticular plant place or property. ,heseare old *gures and old causes. `hange in

causes is always possile. ,hese -actors can e sudi5ided in

many su causes as under7!pars may e mechanical

electrical static due to cutting andwelding etc.

Hot surfa&es may e due toearings and sha-ting sto5es heatersand small appliances petrol keroseneLY+ acetylene or alcohol torches potale-urnaces low torches smoke pipes

chimneys vues and stacks stationaryheating de5ices gas *red appliances 5i.sto5es heaters oilers salamanders etc.

!pontaneous inition is due too6idation o- -uel where air is sucient ut5entilation is insucient to carry awaythe heat as -ast as it is generated.\6posure to high temperature andpresence o- moisture increases thetendency toward spontaneous ignition.xet unslaked lime and sodium chloraterags or waste saturated with linseed oil or

paint sawdust hay grains etc. and

*nally di5ided metals promotespontaneous ignition.

Ha2ardous &(e+i&als and metalslike phosphorous sodium potassiumo6idising materials nitrocellulose *lmand pyro6ylin plastics -uels sol5entsluricants wood paper cloth and ruer

products sprays and mists LY+ andother vammale or e6plosi5e gases areknown -or *re haards.

yperoles pyrophoric sustancesadiaatic compression radiationcatalytic action natural sourceslightening cooking eXuipment electricaldistriution and installation staticelectricity arson ruish playing with*re hand tools pallet material storageand e6plosi5e dust gas 5apour or airmi6ture are all -actors contriuting to *re.

Co++on &auses of industrial ,reand re+edial +easures are gi5en in

,ale Z[.[.

Ta#le 13.3:àuses o- Fire q JemedialUeasures

Cause Re+edial easure

Z \lectricity >tandard and sa-ewiring o5er loadprotection doule

insulation and earthingon portale eXuipment\L` and waterproo-cord in weten5ironment use o-proper vameproo-eXuipment in haardousarea and periodicalinspection

_ ousekeeping

>toring ruish waste oil grease etc. in awastein with closedco5er regular cleaningand inspection und(dyke) to storage tankso- vammale liXuidsdust collectors sa-edisposal incineration.

[ idiìgarretts

osmoking noticesseparate smokingooths checking o-match o6 lighter etc.at security gates.

^ ot +ood insulation

4


5/40

sur-aces -encing ducting -orsmokes and vue.

Friction +ood lurication properelt tension alignmentdust remo5alinspection andmaintenance.

\6cessi5eeat

`ooling temperaturecontrols trainedoperators andsuper5isors.

b xeldingcutting

>pecial place orpartition heat resistantvoor spark controlkeeping vammalesustance away hotwork permitvammaility test in tank

e-ore hot work use o-proper eXuipment.j Flame and

comustion

Yroper design operationand maintenancesucient 5entilationand ignition sa-etyheater insulation hoodchimney keeping vameaway trips andinterlocks.

] >el-ignition

3eeping en5ironmentcool and dry necessary

5entilation andprotection keepingducts and passages o-waste and smoke cleanseparate store o- highlyvammale materialsnot to put oil soakedrags on hot sur-aceslagging and claddingsmall 5essels goodhouse keeping.

Z \6posure arrier wall sprinklerson *re path wire glassin windows.

ZZ Ignitionsparks

Yroper eXuipmentclosed comustionchamer spark arresteron vammale 5ent and5ehicle e6haust varetrip.

Z_ Uechanical sparks

Uachine guarding toa5oid entry o- -oreignparticle -encingmagnetic separator

nonsparking tools.Z[ Uolten hot

sustanceYroper eXuipment withhandles etteroperation andmaintenance nonmi6ing o- water.

Z^ >tatic

electricity(ue toelt dri5epaperfplastic reelinghumanodyvuidisededpneumaticcon5eying

dusthandlingliXuidmi6ingvow in5essel orpipeagitationetc.

+rounding ounding

ionisation andhumidi*cation 5ehicleearthing while trans-erthrough pipelineearthing o- 5esseleXuipment and pipingvow rate reductiona5oiding vammaleatmosphere splashingand settling usingearthed proe

antistatic de5iceconducti5e shoes andvooring copperearthing with earthresistance less than Zohm additi5e to changeliXuid resistancekeeping *lters away-rom storage tankse6tending inlet pipe upto ottom to a5oid -ree-all o- liXuid non

conducti5e parts andearthing o- le5elgauges a5oiding oildrops in water smallsie o- nonconductingplastic containers using_ instead o- `W_ asinert gas electrostaticeliminators onpaperfplastic reelingmachines use o-radioacti5e ionisationetc.

F)RE AN' E4PL5!)5NPHEN5ENA

,o understand these some de*nitionsare necessary.

.1 'e,nitions:

Z. Auto-inition 6spontaneousinition7 te+perature is the

5


6/40

temperature at which a material willsel-ignite and sustain comustion inthe asence o- a spark or vame.

_. Auto+ati& Fire Alar+ !"ste+ is a*re alarm system comprisingcomponents and su system reXuired-or detecting a *re initiating an

automatic alarm -or *re and initiatingother action as reXuired.[. Co+#usti#ilit" 6Fla++a#ilit" or

)nita#ilit"7 is the capacity o- asustance to ignite and continue tourn in the presence o- a heat source.

^. Co+#ustion is a chemical changeaccompanied y the e5olution o- heatand light.

. Control Centre is a permanentlymanned room pre-eraly on groundvoor within the premises at risk -or thereceipt o- emergency calls andeXuipped with communications needed-or transmission o- calls -or assistanceto ser5ices such as *re and police.

. 'etonation is propagation o- vames-ollowing shock wa5e through pipes5essels etc. at a 5ery high speed(supersonic) and high localisedpressure.

b. Explosion is an e6tremely rapidchemical (e6plosi5e) trans-ormation o-

-uel accompanied y release o- energyand compression o- gases capale o- producing mechanical work.

j. Extinuis(in +edia are agentswhich can put out *res. `ommone6tinguishing agents are water carondio6ide dry chemical alcohol -oamhalogenated gases (alons) and water

Vel compound.]. Fire is a rapid o6idationreduction

reaction which results in theproduction o- heat and generally5isile light.

Z. Fire Alar+ !"ste+ is a cominationo- components -or gi5ing an audileand 5isile andfor other perceptilealarm o- *re. ,he system may alsoinitiate other ancillary action. Itincludes manual call points -orinitiating alarm.

ZZ. Fire Point is the lowest temperatureat which a mi6ture o- 5apour and aircontinues to urn when ignited.

Z_. Fire Resistan&e is the aility o- anelement o- uilding construction

component -or structure to -ul*l -or astated period o- time the reXuiredstaility *re integrity andfor thermalinsulation andfor other e6pected dutyin a standard *re resistance test (seeI> [j]).

Z[. Fire Resistin 8all is a wall

capale o- speci-ying the criteria o- *reresistance with respect to collapsepenetration and e6cessi5etemperature rise.

Z^. Fla++a#ilit" li+its 6Explosi9erane7 i.e. the 5alues (upper andlower) e6pressed in percent y5olume o- -uel 5apour in air is therange o- concentration within which aparticular 5apour or gas mi6ture withair will urn (or e6plode) when ignited.elow the L\L the mi6ture is too leanto urn and ao5e the \L it is too richto urn.

Z. Fla+eproof En&losure is anenclosure -or electrical machinery orapparatus that will withstand whenthe co5ers or other access doors areproperly secured an internale6plosion o- the vammale gas or5apour which may enter or which mayoriginate inside the enclosure withoutsuzering damage and without

communicating the internalvammation (or e6plosion) to thee6ternal vammale gas or 5apour inwhich it is designed to e usedthrough any Voints or other structuralopenings in the enclosure. (,he terme6plosion proo- is synonymous).

Z. Flas( #a& occurs when a trail o- vammale gas 5apour or aerosol isignited y a distant spark vame orother source o- ignition. ,he vamethen tra5els ack along the trail o- -uelto its source resulting into *re ore6plosion.

Zb. Flas( ,re is 5ary rapid comustion.Zj. Flas( Point is the lowest

temperature at which a liXuid will gi5eoz enough vammale 5apour at ornear its sur-ace such that its mi6turewith air can e ignited y a spark orvame. It is o- more interest in sa-etythan the *re point.

Z]. Fuel is a sustance that acts as a

reducing agent gi5ing up electrons toan o6idiser (e.g. W6ygen in air) in a

6


7/40

chemical comustion. It may e anelement like caron hydrogenmagnesium etc. a single compoundlike `W methane `^ a comple6compound like wood or ruer ormi6ture like LY+.

_. )nition Te+perature is the lowest

temperature at which ignition occurs ina mi6ture o- e6plosi5e gas and airwhen the method speci*ed in I> bj_is -ollowed. (Flash point is a highertemperature at which the moste6plosi5e mi6ture will ignitespontaneously on account o- theen5ironmental temperature).

_Z. aterial Fa&tor o- a sustance is ameasure o- its energy potential and isa -unction o- vammaility andreacti5ity o- the sustance. ,hevammaility depends upon the vashpoint or heat o- comustion while thereacti5ity depends upon the instailityo- water. igher is the Uaterial Factorhigher is the *re and e6plosion haardpotential o- a particular sustance. Fordetails see FYb^UZ]].

__. !+oe ents are openings *ttedwith manual shutters -or remo5al o- smoke -rom a *re.

_[. !pontaneous )nition or

Co+#ustion occurs as the result o- the gradual de5elopment o- heatgeneration y chemical changes. Fore6ample aggas (grass) cuesheaped to e used as -uel generatesometimes spontaneous comustionwithout spark and resulting into *re.>imilarly oil soaked rags cansometimes ignite without spark due tocomining with o6ygen (o6idation)e5ol5ing heat and i- the heat gi5en oz reaches the apparent ignitiontemperature o- the rags it may urstinto vame and result in *re. xaterspraying can a5oid such phenomenon.

_^. entin Fire is the process o- inducting heat and smoke to lea5e auilding as Xuickly as possile y suchpaths that lateral spread o- *re andheat is checked *re *ghtingoperations are -acilitated andminimum *re damage is caused.

. C(e+istr" of Fire:

For a *re to start four ele+ents areessential7

Z. Fuel (comustile material andreducing agent).

_. 5x"en or o6idant or o6idiser (-rom

the atmosphere).[. Heat or source o- ignition (necessaryto start the *re initially utmaintained y the *re itsel- once it hasstarted and

^. Uaintenance o- &(ain rea&tionthrough -ree radicals.

,hese -our sides constitute a ,rep"ra+id (instead o- the old concept o- *re triangle).

I- any one o- ao5e -our elements isremo5ed the *re goes out. ,here-oremethods o- *re e6tinguishment aredependent on7

Z. Jemo5ing or shutting oz the source o- -uel.

_. \6cluding o6ygen or decreasing itelow Z^ to Zj y adding inertgases.

[. Jemo5ing heat -rom the *re -asterthan its lieration and

^. Jemo5ing -ree radicals to discontinuechain reaction and vame propagation.ry powder chemicals andhalogenated hydrocarons capture-ree radicals and put out *re in thisway.

,hus *re is a rapid chemical o6idationreduction reaction. It is an o6idation o- asustance accompanied y heat lightand vame. ue to incomplete comustionit e5ol5es smoke and caron mono6idewhich creates in5isiility and to6icatmosphere -or *re *ghters.

n e6cess o- air can cool thecomustion gases to Xuench the *re i- the comustile material is smallotherwise it cannot as in case o- -orest*re where the comustile material is toomuch to cool.

,he chemical reaction is e6othermicas it e5ol5es heat and the heat releasedis used -or the reaction to continue.

Fire is a urning or comustionphenomena and the comustion may e

7


8/40

kinetic or dizusi5e depending uponhomogenous or inhomogeneous air-uelmi6tures. ,he comustion may ecomplete or incomplete. ,he completecomustion gi5es product like `W_ >W_water 5apour etc. which cannot urn anymore. ,he incomplete comustion (due to

insucient or locked air) gi5es `Walcohol aldehydes etc. which can urn-urther more.

,he amount o- air reXuired to urn Zkg. o- comustile material (or Z m[ o- gas) is roughly gi5en y { Z.Z_|fZ where | is the heat (or calori*c5alue) o- comustion kf3g. or kfm[. Jateo- urning also depends on the status o- -uel i.e. solid liXuid or gas.

.3 !taes and !pread of Fire:

Uostly *re de5elops in four staes

Z. )n&ipient stae o 5isile smokevame or more heat de5eloped.In5isile comustion particles aregenerated o5er a period o- minuteshours or days. Ionisation detectorsrespond to these particles.

_. !+oulderin stae isile smoke

generation. Yhotoelectric detectorscan detect this smoke.

[. Fla+e stae Flame starts a-ter pointo- ignition. >moke decreases and heatincreases. In-rared detectors candetect this stage.

^. Heat stae eat vame smoke andgases are produced in large amount.

,hermal detectors respond to thisstage.

>ee Yart ._ -or such types o- detectors and alarms.

!pread of Fire:

6A''7

./ Fire Load :

Fire load is the concentration oramount o- comustile material in auilding per sX. mt. o- voor area. It isde*ned as the amount o- heat released inkilo calories y the -uel per sXuare meterarea o- the premises. Fire loads are use-ulto calculate the water reXuirement to

Xuench the *re as when water comes incontact with urning sur-ace it asorsheat. Z cc o- water asors Z cal o- heatwhen the temperature is raised y Z`.

,he -act should also e considered thatall the -uel does not urn at a time and allthe water does not asor heat as it vowsaway.

omay Jegional `ommittee (J`)on *re has prescried rules -or *re loadcalculation. Fire loads are calculated toassess potentiality o- *re haard need o- amount o- *re pre5ention and protectionsystems (e.g. water or other agent) andamount o- premiums reXuired -or *reinsurance. Fire load classi*cation is as-ollows 7

Low *re load less than Z lakh . ,h. .

Uoderate *reload

etween Z to _ lakhs. ,h. .

igher *re

load

etween _ to ^ lakhs

. ,h. .

>ee Jule (ZZ) o- the +uVaratFactories Jules -or area calculation y` -ormula.

>ee Yart ._ o- `hapterZ] -or *ree6plosion and to6ic releases. >ee Yart Z[o- `hapterZj also.

.; Explosion :

Explosion is the result o- rapidcomustion with a sudden 5iolent changeo- pressure in5ol5ing the lieration ande6pansion o- a large 5olume o- gas.

,hus release o- energy in a rapid anduncontrolled manner gi5es rise toe6plosions. ,he released energy mayappear as heat light sound ormechanical shock. `omustile dusts orpowders vammale 5apours andvammale gases can e6plode. comustile material air and source o-

8


9/40

ignition (or temperature) are theprereXuisites -or an e6plosion.

,hus e6plosion is a sudden and5iolent release o- energy. Its ezectdepends on the rate at which the energyis released.

T(ree t"pes of ener" can e

released 7 physical chemical or nuclear.ursting o- tyre 5essel pipe etc. due too5erpressure or rittle -racture andvushing o- superheated liXuid (thermalenergy) are e6amples o- physical energy.`hemical energy is released due tochemical reaction. It may e uni-orm as incase o- a 5essel or it may e propagatingas in case o- a long pipe. \6othermic orrunway reaction decomposition andpolymerisation are also e6amples o- chemical e6plosion. uclear energyrelease can cause nuclear e6plosion.

T"pes of explosion are devagrationand detonation. It is also classi*ed ascon*ned and uncon*ned e6plosionL\\ gas and dust e6plosion.

Explosion 'ata re-ers in-ormationon the e6plosi5e properties o- a materialand is usually gi5en in descripti5e termssuch as low moderate or high.

Explosion (a2ard o- a material cane descried y its 7

Z. >ensiti5ity to mechanical shock orimpact which indicates whether ornot the material will urn or e6plodeon shock or -riction and

_. >ensiti5ity to static discharge whichindicates how readily the material cane ignited y an electric shock.

Explosion (a2ards in process plantsare o- many types. ,hey include (Z) uste6plosions (_) Uolten Uetalwatere6plosions (e.g. induction -urnace) ([) irsystem e6plosions (^) >uperheated liXuide6plosions () Uist and >pray e6plosionsand () `rankcase e6plosions.

Explosi9e li+its speci-y the concern-raction range o- a material in air(percentage 5olume) which will urn ore6plode in the presence o- an ignitionsource. \6plosi5e limits o- some commonchemicals are as under 7

C(e+i&al LEL 607 parks (_) Flames andhot sur-aces ([) >tatic electricity (^)

`ompression and () `hemicals

pyrophoric material unstale compoundsreacti5e compounds and catalysts.E>e&ts of explosion are more

rele5ant to sa-ety prolems. ,hey include(Z) last damageprimary and secondary(_) Uissile damage ([) ,hermal ezects (^)+round shock () `rater and () \zectson people.

!(o&-=a9es due to e6plosion cancause damage to uildings reakingwindows and eVecting missiles o5erdistances o- se5eral hundred metres.Yeople can e lown o5er or knocked

9


10/40

down uried under collapsed material orinVured y vying -ragments. Yeople in the5icinity o- o5erpressure may die andinVuries due to indirect ezects are alsoserious.

T(e e>e&ts of explosion depend onnature and Xuantity o- material in5ol5ed

and the degree o- con*nement o- the5apour cloud. ,he pressure decreasesrapidly with increase in distance. Fore6ample the e6plosion o- a tankcontaining tonnes o- propane results ina pressure o- Z^ kYa at _ mt and apressure o- kYa at mt -rom thetank.

t a pressure o- to Z kYa peoplecan e inVured while structural demolitionand doorsfwindows reaking is possile ata pressure o- [ to Z kYa.

ata on -atality is gi5en y +lasstoneasunder 7

Pro#a#ilit" of Pea o9erpressure6psi7

fatalit" 607 6'uration /??+illise&onds7

Z [^ ^]]

Uuch higher o5erpressures arereXuired to ezect the same le5els o- -atality -or the durations o- the order o- ZZ milliseconds typical o- high e6plosi5es.

ata on eardrum rupture due todirect last ezect is gi5en y \isenergas under7

Pro#a#ilit" of Pea o9erpressure

eardru+ rupture607 6psi7

Z (threshold) _.^Z _.j .[] Z_._

\6tent o- inVury (laceration woundetc.) depends on the weight o- a vying-ragment (g) its density (gfcm_) peakpressure (psi) and impact 5elocity (mfs).ased on these -actors \isenerg

considered a vying glass -ragment o- Zg

with _. gfcm_ density and ga5e-ollowing data 7

T"pe of in*ur" Pressure)+pa&t 6psi7

9elo&it"6+@s7

>kin laceration Z_ Z

threshold>erious wound _[ [ threshold>erious wound ^ proaility>erious wound bj ] Z proaility

Following tale gi5es some historical*gures on e6plosion haard7

$ear

Pla&e C(e+i&al

'eat(s

)n*uries

Z]_Z

Wppau+ermany

mmonium nitrate

^[

Z]^_

,essenderlooelgium

mmonium nitrate

Z

Z]^b

,e6ascity >

mmonium nitrate

_ [

Z]^j

Ludwigsha-en x.+ermany

imethylether

_^ [j

Z]^

iturg+ermany

3erosene [_ Z

Z]b

Lake`harles

Isoutane b Z[

Z]b_

\ast >t.LouisIllinois>

Yropylene _[

Z]b^

ecaturIllinois

>

Yropane b Z_

Z]b^

Fli6orough 3

`yclohe6ane

_j j]

Z]b

eaketherlands

Yropylene Z^ Zb

Explosion Prote&tion and Relief includes the methods o- (Z) Flamearresters and a5oidance o- source o- ignition. (_) utomatic isolation ([)

utomatic suppression (^) >eparation ()`ontainment () enting o- ducts and

10


11/40

pipes (b) enting o- 5essels (j) enting o- reactors and (]) \6plosion relie- o- plantand eXuipment.

'ust Explosion is possile due tovammale dusts o- wood coal-ood(starch vour sugar cocoa -eedstuzs) chemicals plastics (urea

-ormaldehyde resin polyethylenepolystyrene) metals(aluminiummagnesium) etc..

t a starchfcorn plant at èderJapids Iowa in Z]Z] ^[ people werekilled and at Yeking Illinois in Z]_^ ^_people were killed due to dust e6plosion.

t a starch plant at hmedaad _]workers inVured and out o- them _ dieddue to starch dust e6plosion on Z]Z_Z]]Z.

\6plosion characteristics o- dustsuspension as gi5en y F. Y. Lees are asunder7

Z. \6plosiility classi*cation._. Uinimum e6plosile concentration.[. Uinimum ignition temperature.^. Uinimum ignition energy.. Ua6imum permissile o6ygenconcentration

to pre5ent ignition.. \6plosion pressure characteristics.

(a) ma6imum e6plosion pressure.() ma6imum rate o- pressure rise.(c) a5erage rate o- pressure rise.

>ources o- ignition -or dust e6plosionsare (Z) Flames heat or hot sur-aces (_)xelding and cutting ([) Uechanicalsparks (^) >el-heating () >taticelectricity and () \lectrical eXuipment.

Yre5enti5e methods -or duste6plosion include (Z) 5oidance o- dustsuspensions (_) xet process ([)\limination o- source o- ignition and (^)Inserting.

Uethods o- protection against duste6plosion include (Z) Isolation (_)òntainment ([) \6plosion suppressionand (^) \6plosion 5enting.

ust *res can occur in dust depositsand are o- two types vaming andsmouldering *res.

ain +et(ods to pre9ent any typeo- e6plosion are (Z) 5oidance o-

vammale mi6ture y good 5entilationdilution dust collection system wet

methods etc. (_) 5oidance o- sources o- ignition y a5oiding e6cessi5e heating(temperature) elimination o- spark vameetc. using sparkfvame arrester usinge6plosion proo- electrical eXuipment and*ttings and y a5oidance o- staticelectricity a5oiding -riction etc.

espite all such methods i- e6plosionis possile control measures should eadopted such as to limit the spread andezects o- an e6plosion y pro5idinge6plosion relie- de5ices such as rupturediaphragms or e6plosion doorsfwindowspanels or 5ents pro5iding lastwalls orstrong enclosure etc.

Explosion 9entin de9i&es:

\6plosion 5enting is the most widelyaccepted and utilised e6plosion protectionstrategy in use today. arious types o- de5ices are used to pro5ide e6plosiono5erpressure protection such as certi*edrupture panels (e6plosion 5ents) hingedde5ices shear type -asteners homemade (uncerti*ed) 5enting panels lowout panels} and more. Uany o- thesede5ices ozer some redeeming ene*tsut in the end are not reliale ase6plosion protection options.

In 5iew o- the reduced eciency o- hinged enclosures lightweight rupturediaphragms are recommended.

For e6plosion 5enting de5ice thereare *5e important per-ormancecharacteristics to consider7

Z. enting \ciency ~ \cient de5icesreXuire less relie- area andfor pro5idelower 5ented pressures.

_. èrti*ed urst Yressure (Ystat) ~,he5enting de5ice tested and warrantedto open at the identi*ed pressuree5ery time.

[. Wpening Yattern ~ It pro5ide thee6pected relie- area e5ery time.

^. Fragmentation ~ Its operation createdangerous proVectiles.

. Jeliaility ~ It operate properly whenneeded.

. 'eBaration and'etonation:

11


12/40

'eBaration is 5ary rapid autocomustion o- particles o- e6plosi5e as asur-ace phenomenon. It may e initiatedy contact o- a vame or spark ut may ecaused y impact or -riction. It is acharacteristic o- low e6plosi5es.

'etonation is e6tremely rapid sel-

propagating decomposition o- ane6plosi5e accompanied y a highpressuretemperature wa5e that mo5esat -rom Z] mfsec. It may einitiated y mechanical impact -riction orheat. It is a characteristic o- highe6plosi5es which 5aries consideraly intheir sensiti5ity to shock nitroglycerineeing one o- the most dangerous in thisregard.

evagration or detonation is a -ormo- e6plosion the -ormer is due to lowurning 5elocity (vame speed as Z mfs)while the later is due to high urning5elocity (vame speed as _[ mfs). detonation generates high pressure andis more destructi5e than a devagration.

,he peak pressure caused y adevagration in a closed 5essel can reachup to bj kYa (j ar) whereas in caseo- detonation it easily reaches up to _kYa (_ ar).

devagration can turn into a

detonation while tra5elling through a longpipe. In that case devagration 5elocitye6ceeds that mentioned ao5e.

xhether a devagration or detonationtakes place depends on the materialin5ol5ed and the conditions under whichit occurs. 5apour phase e6plosionreXuires some degree o- con*nement -ora detonation to take place.

etonation o- a gasair mi6ture ispossile directly y a power-ul ignitionsource or y transition -rom devagration.>uch transition reXuires a strongacceleration o- the vame -ront. It ispossile in pipelines ut rarely possile in5essels.

numer o- sustances are listedwhich can produce detonation in gasairmi6ture. >ome commonly known are 7

cetone \thylenecetylene ydrogenenene Uethane`hloro-orm Uethanol

`yclohe6ane aphthalene

iethyl ether ,richloroethylene

etonation usually occurs at wellelow the upper e6plosi5e limits.>eparate 'etonation Li+its area5ailale -or some sustances as under7

!u#stan&e

'etonationLi+its607

Explosi9e li+its607

Lo=er


13/40

r l 6t7 s

Z]b

Lake`harlesLa.

Isoutane ^ b

Z]j

Yernisetherlands

ydro`aron

Z^ _

Z]b

YortudsonUiss

Yropane _]

Z]b^

Fli6orough3

`yclohe6ane

_ _j

ata on eXuipment in5ol5ed in `\name process eXuipment storage tanktransportation 5ehicle and modes o- release as 5essel -ailure piping 5al5es or

*ttings -ailure release -rom 5enting-acilities etc.>ome Xuestions o- empirical

approach re-erred y F.Y. Lees are asunder 7

Z. FreXuency o- release._. Uass o- material released.[. Fraction o- material 5aporised.^. Yroaility o- ignition o- cloud.. istance tra5elled y cloud e-oreignition.

. ,ime delay e-ore ignition o- cloud.b. Yroaility o- e6plosion rather than *re.j. \6istence o- a threshold Xuantity -or

e6plosion.]. \ciency o- e6plosion.

e has also discussed the -ollowingtheoretical prolems 7

Z. \6istence o- detonation limits._. Wccurrence o- uncon*ned detonations.[. irect initiation o- detonation.

^. `haracteristics o- vame propagation.. ,ransition -rom devagration todetonation.. ir entrainment andb. `haracteristics o- devagration lastwa5e.

`\ due to hydrogen are unusualut did occur. ydrogen 5enting should edirectly to atmosphere 5ia multiple 5entsor y a vare.

Uethane at normal temperature urnut do not e6plode. apour cloud o- L+

might e6plode.

. LEE:

oiling liXuid e6panding 5apoure6plosion (L\\) also re-erred as a*reall is a comination o- *re ande6plosion with an intense radiant heat

emission within a relati5ely short timeinter5al.

xhen a tank or pressure 5esselcontaining liXuid or liXue*ed gas ao5e itsoiling point (so heated) -ails or rupturesthe contents release as a turulentmi6ture o- liXuid and gas e6pandingrapidly and dispersing in air as a cloud.xhen this cloud is ignited a *realloccurs causing enormous heat radiationintensity within a -ew seconds. ,his heat

is sucient to cause se5ere skin urnsand deaths within a -ew hundred metresdepending on the mass o- the gasin5ol5ed. L\\ in5ol5ing a tonnepropane tank can cause thirddegree urnat • _ mt and listers at • ^ mt.

Joadfrail accident to a tankcarfwagon or due to weakening o- structure y *re or physical impact on ao5erstressed 5esselftank can cause aL\\.

>ome reported maVor L\\

e6amples are as under 7

$ear

Lo&ation

C(e+i&al

'eat(

)n*ur"

Z]

FeyinFrance

LY+(Yropane)

Zj ]

Z]]

LaurelUiss

LY+ _

Z]b

`resent`ity Ill

LY+

Z]bZ ouston,e6 inylchloride Z

Z]b_

ew ersey

Yropylene

_

Z]j

Ue6icocity

LY+ _

>ee Yart .̂ . o- `hapter_^ -ormathematical e6pressions.

3 CLA!!)F)CAT)5N 5F F)RE

AN' E4T)NG


14/40

,ale Z[.^ and Z[. gi5e the classeso- *re ( to \) and portale *ree6tinguishers necessary -or them.

Ta#le 13./ : `lasses o- Fire and\6tinguishers

Classof

,re

'es&ription

Extinuis(in ediu+

)!No.

Firesin5ol5ingordinarycomustilematerialslike woodpaperte6tiles*res and5egetalesetc. wherethe coolingezect o-water isessential -orthee6tinction o- *res

xater >odaacid typexater type(gaspressure)xater type(constant airpressure)nti-reeetypes andxateruckets

][^

]^

_[^

Fire in

vammaleliXuids likeoils greasesol5entspetroleumproducts5arnishespaints etc.where alanketingezect isessential

`hem. Foam

àrondio6ide

ry Yowder

ry YowderUechanical-oamalon Z_ZZ>anduckets

][[

bZ^b

^_jbj

jZ^]

_ZbZ

^[j

Zj

Z_^

ZZZj

` Firesin5ol5inggaseoussustances

underpressure

àrondio6idery Yowderry Yowder

alon Z_ZZ

_jbj

jZ^]

_ZbZ

where it isnecessaryto dilute theurning gasat a 5ery-ast ratewith an inert

gas orpowder

^[j

ZZZj

Firein5ol5ingmetals likemagnesiumaluminiumincpotassiumetc. wherethe urningmetal isreacti5e towater andwhichreXuiresspeciale6tinguishing media ortechniXue

ry powder>pecial drypowder -ormetal *re

>anduckets

_ZbZ

^jZ

ZZj[[

\ Firesin5ol5ingelectrical

eXuipmentwhere theelectricalnonconducti5ityo- thee6tinguishing media iso- *rstimportance

àrondio6idery

chemicalpowderalon Z_ZZxhenelectricaleXuipmentis deenergisedsame as -or`lasses q>anduckets

_jbj

_ZbZ^[j

ZZZj

ote 7 For other I> see Yart ^._ o- this`hapter.

Ta#le 13.; : ,ypes o- \6tinguishers andsuitaility -or Fire (I>7_Z])

T"pe of )! For t"pe of Fires

Extinuis(er

No. A C '

Z >oda acid

type

][^

>

€

>

€

> >

14


15/40

_ xater type(gascartridge)

]^

> > > >

[ xater type(storedpressure)

_[^

> > > >

^ `hemical

-oam type

][

[ b

Z^b^

> > > >

Uechanical-oam type

Z_^

> > > >

ry powdertype

_ZbZ

Zj

> > > >

b ry powder

type

ZZj[

[

> > > >

j `W_ type _jbj

jZ^]

> > > >

] alon Z_ZZtype

ZZZj

> > > >

€ > { >uitale > { ot >uitale

>ee Yart .[.Z -or the use o- e6tinguishers.

/ !TAT


16/40

*re y Z >egregated electrical machinery or

y keeping them vame or e6plosionproo-.

_ 5oidance o- static charge to adangerous e6tent.

[ on-errous shoes to a5oid sparks

y -riction.^ Yrohiition o- smoking lighting orcarrying matches or lighters etc.

,ransmission elts without iron-asteners.

5oidance o- open vames sparkso5er heated sur-aces radiant heatand ignition -rom physical orchemical reaction.

; !pontaneous inition :Z 5oid air pocket and ensure good

5entilation._ >a-e distance in heaps o- material

susceptile to *re.[ Wpen ground storage at minimum

distance o- Z mt -rom process orstorage uilding.

Gas C"linders :Z Jooms shall ha5e adeXuate

5entilation._ Wpen storage to e protected -rom

direct sunrays e6cessi5e heatcontinuous dampness and away

-rom highly vammale sustances-urnaces and hot processes. !torae of Fla++a#le Liuids :

Z |uantity minimisation._ >uitale containers with closed

co5ers.[ LiXuid o- F.Y. elow _Z ` shall not

e stored more than _ litres in anyroom.

^ Fire resisting construction with *rewalls and sel- closing *re doors.

>torage o- large Xuantities as perYetroleum Jules Z]b. ndergroundstorage is pre-erred.

>teps to pre5ent leakage. Fla++a#le dust as 9apour

=aste et&. :Z >teps to remo5e or pre5ent

accumulation to dangerous e6tent._ aily disposal.[ Uetal containers with co5ers.

Fire Exits :n e6it includes doorway corridor and

passageway. It should pro5idecontinuous (unostructed) and sa-e

egress (departure) y *re resistingwall. Li-ts escalators and re5ol5ingdoors are not considered as e6its}.

!o+e spe&i,&ations of Fire Exitsare as under :

Z. ,hey should e sucient in numer._. `learly 5isile and illuminated.

Lighting independent -rom normalpower supply.

[. Uarked y language understood ythe workers.

^. Iron or spiral ladders not allowed.. oors or roller shutters near li-t or

stair entrance should e o- *reresisting type to pre5ent spread o- *re or smoke.

. ll e6its should reach open spaceleading to a street.

b. >hould not e located at a tra5eldistance e6ceeding [ mt. For highhaard storage distance should note6ceed __. mt and at least twoescape routes should e a5ailale ineach such room. >uch more e6itsshould e remotely placed -rom eachother and pro5iding access inseparate directions.

j. Wccupants per e6it o- cm widthshall e -or stairs and b -ordoors.

]. rea o- Z m_ per person or actualnumer o- occupants as stated in (j)ao5e whiche5er is more shall econsidered to determine numer o- e6its.

Z. \5ery voor ao5e or elow theground voor shall ha5e minimum twoe6its. Wne o- them should ha5einternally enclosed stairway.

ZZ. Uinimum dimension o- doorway width Z cm height _ cm.

Z_. \6it doorways should openoutwards at all times. In an opencondition it should not reduce thewidth o- stairway or landing less than] cm. W5erhead rolling shutters notallowed -or this purpose.

Z[. \6it door should ha5e a minimumlanding o- Z.m 6 Z.m on the samevoor e-ore opening on any stairway.

Z^. \6it door should e openalewithout key.

16


17/40

Z. xidth o- corridorfpassagewayshould not e less than total widthso- all e6it doors opening on it. eighto- corridorf passageway shall emore than _.^ mt.

Z. I- a staircase is arranged round ali-tway the *re resistance (rating) o-

the li-t way should e more than thato- the staircase.Zb. ollow comustile construction

is not permitted.Zj. >taircase dimensions Uinimum width Z cm.Uinimum width o- tread _ cm.Ua6imum height o- riser Z] cm.Uinimum height o- hand rail Z

cm. ,reads should e nonslipperyumer o- risers not more than Z_ per

vightand rails should e *rmly supported.Z]. se o- spiral staircase is limited

to low occupant load and -or auilding not higher than ] mt. Itsdiameter shall e more than [ mt.with adeXuate headroom.

_. t least one *re door on the samevoor should e o- sel-closing type.

_Z. Floor area on the opposite(shelter or re-uge) side o- a

horiontal e6it should e sucient toaccommodate occupants o- the voorarea ser5ed allowing more than .[m_ per person. t least one e6itshould directly lead to the street.

__. Jamp o- slope Z in j or less epro5ided to connect voors o- dizerentle5els.

_[. staircase may e sustitutedy a ramp o- slope Z in Z or less.>ur-ace o- ramp should e nonslipping.

_^. I- the uilding capacity is morethan persons or i- more than _persons are employed ao5e orelow the ground voor an automaticor manual *re alarm system shall epro5ided.

1? First Aid Fire Fi(tinArrane+ents :

>uitale and sucient *rst aid*re e6tinguishers as prescried in>chedule I (similar to ,ale Z[.^)

shall e pro5ided and maintained. ,hey should con*rm to I>. ,heir

numers and types are classi*ed -or*re class to \. ,hey should esimilar in a shape appearance andmethod o- operation. ,hey shoulde placed in conspicuous placereadily and easily accessile. ,heirottom should e b cm ao5e the

voor le5el. ,hey should e chargedregularly and rechargedimmediately a-ter discharge. xaterand sand should e clean. Wne ]litres waterucket should epro5ided -or e5ery Z m_ o- thevoor area or part thereo-. For detailssee >ch. I.

11 5t(er Fire Fi(tinArrane+ents :

-ormula is suggested tocalculate the amount o- *re water. I- this reXuirement is litresfmin ormore power dri5en trailer pumps o- adeXuate capacity are prescried.Yumping capacity e reduced y_ i- *re ser5ice is a5ailale within[ km. \ach trailer pump shouldha5e eXuipment stated in >cheduleII. ,hey should con*rm to I>. Itshould e housed in a separateshed close to a principal source o- water and near the main risk o- the

-actory. ,owing attachment one -ore5ery ^ trailer pumps is reXuired i- manual pulling and placement o- pump is not possile.

xater should e sucient tosupply at least -or Z minutes. tleast o- the water reXuirementcalculated y the -ormula or^ litres whiche5er is lessshould e stored in static tanks(each o- ^ litres or more)distriuted round the -actory and in*re prone area. iameter o- mainpipe should e more than Z cmcapacity more than ^ litfmin andpressure more than b 3gfcm_.

1 Fire Fi(tin Tea+ 'rill et&. :ll *re *ghting eXuipment

(portale and *6ed) shall e incharge o- a trained person. ,heirnumer should e sucient andpro5ided with necessary clothingand eXuipment including helmets

elts gum oots.|uality o- personal protecti5e

17


18/40

eXuipment (YY\) should con*rm tothe I>.

Fire drills are reXuired at leastonce in two months or as o-ten asnecessary.

13 H"drants and !prinlers :Fire hydrants and automatic

sprinklers shall e in addition andnot in sustitution o- ao5ereXuirements.

>ee Jules ZbZ to ZjZ o- theYetroleum Jules Z]b in Yart _.Z o- `hapter_j also.

/. )ndian !tandards :

Fire : I> on *re sa-ety are many.

,hey can e selected as per reXuirement-rom the I> andook. -ew standardsare stated elow 7

+lossary o- terms -or FF\ bb[ jbbFire appliances *rstaid selectioninstallation and maintenance _Z] Fireell ]_j Fire rigade trailer pump ]^_]^[ q ]^^ Fire control eXuipment Z^jFire detectors heat sensiti5e _Zb Fireescape wheeled ][Z Fire e6tinguishersportale `W_ type _jbj ry powder type_ZbZ Uechanical -oam type Z_^ ][[^]j] ^_ xater type (gas cartridge)]^ xater type (stored pressure) _[^xater type ucket pump ]_^ gaspressure ]^ >oda acid type ][^ Firee6tinguishing system `W_ *6ed [j_ Fire*ghting appliance selection operationand maintenance j] \6tension ladders][ Flame and heat resistant suit bZ_xater tender type -or *re rigade use]^j +as cartridge -or use ^]^b Je*lls -orportale *re e6tinguishers ^] (Yart Z to

^) ,win `W_ *re e6tinguishers (trolleymounted) jZ^] Z litre *re engine-oam type Z^b^ igher capacity drypowder (trolley mounted) ZjYortalealon Z_ZZ type ZZZj. Firetenders ]^ to ]Z ]^ to ] _][b Z^ Z]][.

utomatic *re detection and alarm_Zj] eat sensiti5e *re detectors _Zbydrants in multistorey uilding [j^^xater supplies -or *re *ghting ]jutomatic sprinkler heads ]]b_.

oses òuplings ccessories [jj^ ]Z to ]Z ]_ to ]_j Z_ bZ^_ j] ydrantstand post type ]j>tand post water monitor j^^_ ydrantsand hose reels [j^^.

Fire sa-ety in uilding Z^Z to Z^^Z^ Zj]Z +inningpressing -actories

_b_ xelding q cutting [Z òttonte6tile mills [b] ute mills [j[>torage q xarehouse []^ *reresistance test [jj [j] tea -actories^jj *re retardant plywood ] sawmills and woodworks [_] test -orignition temperatures bj_ paint and5arnish -actories ]Z] chemicalindustries ZZ^b vour mills Z[^ caleruns Z_^] li-e sa5ing eXuipmentsymols Z^j LY+ storage installations^^ graphic symols Z_[b sa-etysigns Z_[^] gas testing vame sa-etylamps bbb.

Explosion : >ome I> on e6plosionare7 `lassi*cation o- haardous areasb_ \6ploders ]j_. \6plosion haards protection against jb \6plosi5e andaccessories lasting tests ]\6plosi5e atmosphere electricaleXuipment j_[] to j_^Z b][ bb_^j]^ \6plosi5e industry ZZbj[\6plosi5es or pyrotechnic glossary

ZjZ Yackages Z_Z_ de6trin Z__bYotassium nitrate [Z >odium nitrateZ_jZ mmonium nitrate ^j ariumnitrate ^[] luminium powder ^[jarium chromate bjj Lead chromateb_ Uanganese dio6ide bZ[ àlciumcaronate b[[.

>ee also Yart[ o- `hapterZZ -orelectrical eXuipment to e used invammalefhaardous areas. I> b_ -orclassi*cation o- haardous areas ha5ingvammale gases and 5apours and I>bZ -or selection o- electrical eXuipment-or such areas are most rele5ant.

/.3 Guidelines of ReionalTari> Ad9isor" Co++ittee6TAC7 :

Fire Yrotection Uanual or ooklet onrules go5erning *re protection systemswas *rst pulished in Z] y theàlcutta Fire Insurance ssociation andthe last edition o- Z]][ is pulished y

18


19/40

the Wriental Insurance ò. Ltd. omay_. ,he òmmittee means the Jegionalòmmittee at the regional oce o- the

,ariz d5isory òmmittee (,`). ,hesuVects o- manual are as under7

Yart I7 Internal ppliances Fire

enginesf,railer pumps utomatic*re alarm systems and ydrantsystem.

Yart II 7 xater >pray >ystems.

Jules -or utomatic >prinklerInstallations are also a5ailale.

,ale o- contents o- Yart I is as under7

Fire enines pu+ps alar+s and("drants 6TAC Rules7:

Z.

JeXuirements regarding sumission o- plans

_.

Yrocedure to e -ollowed in the caseo- application -or discounts

[.

òmmittees inspection staz

^.

Internal appliances

^.Z and appliances^._ >mall ore hose reels

.

Uechanically dri5en *re engines and

trailer pumps.

Jules regarding automatic *re alarmsystem using heat detectors

b.

ydrant ser5ice

b.Z +eneralb._ `lassi*cation o- occupanciesb.[ xater supplyb.^ Yumpsb.^.Z +eneralb.^._ >team dri5en pumpsb.^.[ \lectrically dri5en pumpsb.^.^ Yetrol or motor spirit engine

dri5en pumpsb.^. òmpressor ignition dri5en

pumpsb. Uainsb. ydrantsf*6ed monitorsb.b ose pipes and nolesb.j Foam compoundsb.] Fire *ghting personnelb.Z Uaintenanceb.Z.

Z

Yumps

b.Z. Uains

_b.Z.[

ydrants

b.Z.^

ose pipes and noles

b.ZZ Ueasure to e taken wherethe installation is -or any

reason temporarily inoperati5ej.

ydrant protection -or high riseuildings (nonindustrial)j.Z pplicationj._ òmponentsj.[ Fire rigade

].

ydrant protection o- òtton +in andYress -actories].Z Jeser5oir]._ Yumps].[ Uains].^ ydrants]. ose pipes and noles]. Fire *ghting staz

,alesZ.

\zecti5e capacity o- reser5oir

_.

àpacity -or hydrant ser5ice

[.

>ie o- pipe mains

ppendi6

I pplication -or *re e6tinguishingappliance(s) discountII +uarantee regarding *ree6tinguishing appliancesIII etails o- *re e6tinguishingappliancesI èrti*cate -rom insurers engineer Fire drills registerI xater pressure tale

,ale o- contents o- Yart II is as under7

8ater !pra" !"ste+s 6TAC Rules7:

e*nitions and ,erminology

>ection Z

Yrocedural reXuirementsregarding sumission o- plansand application -or a5ailingdiscounts

>ection _

òmmon reXuirements toigh 5elocity and Uedium

elocity xater >pray >ystems_.Z xater >upplies

19


20/40

_._ Yumps_._._ \lectrically dri5en Yumps_._.[ òmpression Ignition \ngine

ri5en Yumps_.[ etection >ystem_.^.Z Yiping_.^._ Fittings

_. eluge al5es_. rainage

>ection [

igh elocity xater >pray>ystems

[.Z Introduction[._ ,rans-ormer Yrotection[._.Z \lectrical ̀ learance[._._ xater >upplies[._.[ +eneral Layout and esign[._.[.^ YroVectors[._.[. Fire arrier xalls[._.[. >ystem esign[._.^ etection system -or

trans-ormers[._.^.Z Wutdoor ,rans-ormers[._.^._ Indoor ,rans-ormers[.[ Uiscellaneous protection

>ection ^

Uedium elocity xater >pray>ystems

^.Z Introduction^._ xater >upplies

^.[ Yumping ̀ apacity^.^.^ esign density^.^. Layout o- protection network^.^..b \Xuipment protection^.^. >tructural protection^.^.b Yiping and supports^.^.j ydraulics^.^.] etection system^. Yrotection o- oriontal

`ylindrical >torage essels^. Yrotection o- ertical

`ylindrical >torage essels^.b Yrotection o- spherical

5essels^.j àle +alleries and ,unnels^.] òn5eyors

>ection

YrecommissioningYrocedures

.Z Yrecommissioning andacceptance test

._ Yeriodical testing andmaintenance

.[ Yeriodical testing andmaintenance chart

.^ ydraulic calculations+eneral

>ection

+eneral in-ormation

.Z igh 5elocity water spraysystem

._ Uedium 5elocity water spraysystem._.^ >cope o- pplications._.^.Zb Limitations

ppendi6 I II q III

>ee Yart .[._ -or -urther details o- xater>pray >ystem.

>ee Yart [._ o- `hapterZZ -or the ,`Jegulations -or the \lectrical eXuipmento- uildings. ,` rules -or >egregation o- uildings are also a5ailale.

/./ NFPA Code 6NFC7 :

FY means ational Fire Yrotectionssociation o- >. FY is aninternationally recognised ody and theirstandards codes and manuals are-ollowed not only y merican+o5ernment and industries ut also yother countries in the world. F` means

ational Fire òde. ,he code indicates (Z) relati5e risk to

health (_) vammaility ([) instailityand (^) possile speci*c haards(symols) . \ach o- the *rst three aspects(Z) to ([) is assigned a 5alue in the range^ the higher numer indicating higherrisk.

,he content o- the FY code (F`) is5ary e6hausti5e. -ew suVects o- Z]]F` contents are gi5en elow7

ccreditation o- Fire Yrotection\ducation Yrograms ir operations -or-orest ush and grass *res ircra-t *rein5estigators manual Fire *ghting atairport irportfcommunity emergencyplanning lternati5e approaches to li-esa-ety mmonium nitratestorage o-aled cotton storage lower and e6haustsystems uilding materials testmethods *re retardant coatings etc. Fire*ghting in speci*c chemical industriesYrotecti5e clothing -or *re *ghting

\mergency 5oicefalarm ùtting and

20


21/40

welding processes Fire e6tinguishers dizerent types \lectrical code ational\lectrical sa-ety reXuirements \6plosionpre5ention systems Fire department Wccupational sa-ety and health programsFire dept. >a-ety ocer Fire detectorshose etc. Fire Inspector Fire ocer Fire

Yre5ention `ode Fire pumps Fireser5ices Fireworks Flammale andcomustile liXuids gases solids Floorco5ering systems Foam systemsFootwear Fuel +as `odeationalaardous materials incidentsresponders ealth care -acilities omesand camps in -orest areas ydrants Li-e>a-ety code Lightning Yrotection codeL+ and LY+ storage and handlingUarine terminals reathing apparatusYersonal alert sa-ety systems (Y>>) -or*re *ghters Ylaces o- worship Yropertysur5ey manual Jecordsprotection o- Joll paper storage Joo- co5erings *retests o- >ignalling systems >moke andheat 5enting >pray and sprinklerssystems >tatic electricity >ymols *reprotection ,ruck *re protection entingo- devagrations xater supplies xettingagents xild*re control xood duste6plosion and irconium productionprocessing.

,hus FY code gi5es standards -ormany suVects on *re.

; 'E!)GN F5R F)RE!AFET$

;.1 Fire Resistan&e of uildin aterials :

In vammale area when uilding

materials and paints are used theyshould ha5e good *re resistance. >teeland masonry are *re resistant materials.Fire resisti5e structural material should eselected depending upon the type o- *repossile. ,here are three types o- materials 7 (Z) onvammale 5i.metals rick clay asestos concretecement gra5el ceramics sand etc. (_)ardly vammale 5i. staw rick drygypsum plaster *reoard linoleum etc.([) Flammale 5i. organic origin such as

wood cardoard -elt paper etc. s -ar as

possile nonvammale material shoulde selected.

Fire or Ba+e resistan&e is thecapacity o- structural element to per-ormits loadearing and enclosing -unctionsi.e. to retain its strength and aility towithstand action o- *re -or a particular

time during *re. ,he *re resisting limits o- uildingsshould e high to ensure sa-ety andescape in case o- *re. >uch limits aremeasured in terms o- time (h) -rom thestart o- the *re to the indication o- anycrack or loss o- load carrying capacity(collapse) or rise o- e6cessi5etemperature. ,he *re resisting limits alsodepend on the sie (thickness and crosssection) and the physical properties o- the uilding material. For e6ample Z_ cmthick wall can withstand *re -or _. h anda _ cm thick wall -or . h. Fire retardantcoatings on wood and vame proo*ng o- -arics are use-ul to some e6tent.

S:1'$27 3=)>7 3&>$7 3=7 3=> and'32> pro5ide -urther details.

;. Fire !afet" of uildinPlant Exit Euip+ent et&. :

,he uilding should e protected othhoriontally and 5ertically -rom spread o- *re through voors stairs walls5entilating ducts etc. Fire resistantarriers can e used -or this purpose.

A ,re stoppin is a *recheck wallo- nonvammale material with a *reresistance limit o- at least _. h. It maye lind or with *re resisting doors orgates. >topping can e internal e6ternalroo- and separate (stand alone) *reproo- walls. ,hey are constructed to intersect

the voors ceilings and roo-s with*reoard o- [ cm o5er roo-s -rom nonvammale materials. Fireresistance limito- doors and gates in stopping should emore than Z. h. ,he total area o- suchopenings should not e more than _ o- the total sur-ace area o- the stopping.

xhere the construction o- stopping isnot possile ,re &(e&-2ones (strips o- nonvammale materials) should epro5ided to di5ide voors and walls intosections more than m wide. entipanes

or smoke escape windows should e

21


22/40

pro5ided to -acilitate smoke remo5alduring *re. \6its and escape ways shoulde as per statutory reXuirement. xidth o- escape should e more than a meter andshould increase depending upon thema6imum persons likely to use it.

igh *re risk areas‚ storage packing

and dispatch areas oiler and -uel roomstrans-ormer room kitchen and car parksshould e separated y *re resistantconstruction. >torage o- vammale liXuidsand gases should e minimum possile.+as cylinders should e stored either inopen air with shade or in a room o- nonvammale construction and 5entilatedpermanently to the e6ternal air. Firehaards o- storage o- e6plosi5e andvammale sustances electricaleXuipment static electricity heatingprocesses painting sparkling etc. shoulde -oreseen and -ully protected.

Li(tenin prote&tion o- uildingsis most important as the hea5y electriccharge (up to Z 3 and _ 3)may pro5e destructi5e causing *re ande6plosion in the ground structure.ppropriate lightening arrester (protector)should e *tted higher than the highestoVect and co5ering the lighteningprotected one. ,he resistance o- the

grounding de5ice should e less than Zor _ ohms depending upon its category.Fire safet" should e well thought o-

-rom siting and location stage to themaintenance stage as -ollows 7

Siting and location 7 sucient spacewater and emergency -acilities ezects o- past disasters location o- process areas-or Xuick 5apour dispersal and location o- control rooms.

Plant layout 7 >egregation o- haardous processes and storagedrainage and compliance o- statutorystandards.

"esign and Construction 7 Jelie- 5al5es ypasses rupture discse6plosion 5ents sa-ety interlocks vamearresters vameproo- *ttings selection o- material *re resistant constructionunderground storage.

Plant ?peration 7 Limited storage o- vammale materials good housekeepinggood 5entilation work permit system

emergency action plan and training o- employees.

Plant 6aintenance 7 Jeliaility and-ailure o- monitoring proceduresinspection testing and pre5enti5emaintenance spares a5ailaility andmaintenance o- -ailsa-e sa-ety de5ices.

S:1'$27 3&>$7 '32>7 1'$' andS:21>= must always e -ollowed -or

material and details o- construction o- uildings storage and use o- portale *ree6tinguishers.

F)RE PREENT)5N AN'PR5TECT)5N !$!TE!

road classi*cation o- *re sa-etysystem is e6plained elow 7

Fire !afet"

(\6istence o- *re haard and awakening o-*re consciousness o- themanagement)

Fire Yre5ention

etection y etectors(alarms)\limination o- haard or sourceo- ignition

`ontrol o5er comustiles in

storage handling and process

Fire Yrotection

Fire resistant design o-uildings eXuipment meanso- escape and *6edinstallations

>uppression \6tinguishmentor control y 5arious

e6tinguishers

Fire Fighting

\Xuipment and hardware

>taz training and readiness

o5e steps are e6plained elow 7

Fire pre9ention 7 ,his is an acti5itydirected towards elimination o- possile

22


23/40

and potential sources o- *res. It mainlyindicates measures to a5oid inception o- *res. xhere the source cannot eeliminated or a5oided e6ercise sucientcontrol to ensure its sa-e usage. ,heacti5ity also in5ol5es control o5erhandling storage and process o-

comustiles.Fire Prote&tion 7 ,his is an acti5itydirected towards limiting the spread o- *re to its place o- origin y resorting todesign compartmentation utilisation o- *re resisti5e materials pro5isions o- sa-emeans o- escape control y portale and*6ed automatic e6tinguishing systems.

Fire protection eing wider termincludes *re pre5ention stated ao5e and*re *ghting mentioned elow. Firedetection pre5ention e6tinguishment orcontrol all aim to protect plant peopleand property.

Fire protection engineering is a highlyde5eloped specialised ranch o- engineering and a degree o- .\. (Fire) isawarded in college at agpur. >uchXuali*ed *re engineer and i- he is nota5ailale Xuali*ed sa-ety ocer shouldlook a-ter *re protection acti5ities.

Fire Fi(tin 7 ,his is an acti5itydirected towards pro5isions o- proper *re

*ghting eXuipment proper maintenancepersonnel with proper organisationtraining programme and readiness to*ght *re.

!al9ae 7 ,his is an acti5ity tominimise the damage due to *re smokeand water to the unin5ol5ed property.

Return to nor+al&" 7 ,his iscontingency plan where the 5arious stepsare laid down to ring ack the industryto producti5e stage -rom the cripplingdamage due to the *re.

>ome systems are as -ollows 7

.1 General Controleasures :

ain steps in controlling *re are 7

Z. ,o detect the *re at the earliestpossile.

_. ,o con*ne the *re and[. ,o e6tinguish the *re at the earliest

possile.

!ix funda+ental prin&iples o- *re

pre5ention and reduction are 7

Z. Fire pre5ention engineering._. Jegular periodic inspection.[. Yre5ent the start o- *re.

^. \arly detection and e6tinguishment.. Limiting the spread and damage dueto *re and *re control.

. Yre5ention o- personal inVuries -rom *reor panic including prompt and orderlye5acuation o- personnel.

ased on *re chemistry e6plained inYart _._ four funda+ental +et(ods o- *re control are 7

Z. \liminate the o6ygen o- the air._. Jemo5e or shut o- the -uel supply.[. Jeduce the temperature elow the

kindling point and^. reak the chain reaction continuing

the *re.

,o achie5e the most ecient *reprotection system in5ol5ement o- theuilding designer(architect) andcontractor local authority (uran planer)interior designer structural engineer

electrical engineer *re detection systemmanu-acturerfsupplier uilding sa-etyengineer and local *re marshal isnecessary.

n automatic sprinkler systemecomes most use-ul as it starts initially.\arly detection o- *re speedy responsetrained staz emergency planning andpreparedness and *6ed e6tinguishingsystem ased appropriately on *re loadare the essential key points in any *re*ghting arrangement.

,o stop the *re occurrence -ollowing,re pre9ention a&ti9ities are desired7

1. Fire )nspe&tions 7 Fire prone areaeXuipment and conditions should einspected. Yeriodicity may e dailyweekly monthly etc depending onreXuirement. check list should edesigned est *tting to the premisesand acti5ities. It should includechecking o- poor housekeeping

accumulation o- dust or vammalematerial readiness o- *re hydrants

23


24/40

hoses sprinklers alarms detectorswater storage pumpsfenginescharged portale *re e6tinguishers-oam caron dio6ide `Y and otherprotection systems *re doors aislese6its control room electricaleXuipment hot processes and

machinery and placement o- *re*ghting and personal protecti5eeXuipment tools etc.

. Hot-=or per+its 7 Uany *res ha5etaken place while doing hotwork invammale areas. hotwork permit-orm and tag should e designed andused to check all points in ad5anceand to take necessary precautions.Following steps are use-ul7

Z. `heck the area where work is to edone.

_. List steps eXuipment andprocedure necessary and preparethe permit.

[. xhile at work constant watch(super5ision) is necessary i- haarde6ists.

^. >tandy workers should e ready onthe spot with *re e6tinguishers.

. Isolate vammale materials (stopits vow i- possile) -rom sources o-

ignition.. Isolate sources o- ignition y allpossile ways.

b. >top unauthorised use o- sparkproducing eXuipment neary.

3. Fire #riade and 'rills 7 plant *rerigade o- Xuali*ed and trainedpersonnel is necessary to *ght *re tilloutside pulic *re rigade arri5es andhelps.Jegular scheduled training o- allmemers o- the unit should e carriedout. Wnsite emergency plan in5ol5ingother employees should e preparedand rehearsed.

/. Fire-retardant treat+ents 7 >uchcoatings can e applied on woodplastics paper etc. to withstand vame.Fire rating o- such sustances shoulde studied -or comparison to the nontreated material. `hemical treatmentto -arics reduces their vammaility.

Flame retardant can5as can e usedup to _ `. For higher temperatures

asestos or chrome leather ispre-erred. xater gel compound can eused to soak a clothpiece to make it*reretardant. It should e noted thatall such treatments are temporary andnot -oolproo-.

;. Co++uni&ation 7 -ter noticing a *re

-ast communication is necessary tocall -or *re *ghting team and to alertoccupants to the emergency. xellarranged ells *re call uttons or acoded computerised *re alarm systemare essential. \Xually important is thetraining o- persons to react a-terhearing the alarm.

. Prote&tin near#" #uildins 7 -ternoticing a *re it is also necessary toprotect the adVacent plant and uildingy closing windows positioningpersonnel at each window nearest the*re with *re e6tinguishers or *rehoses and stationing *re *ghters onthe roo- o- the e6posed uilding withhose lines to keep the roo- wetted andto put oz any local *re.

. Assess+ent of Fire Riss 7 Forezecti5e *re protection it is necessaryto analyse and e5aluate the *re risk.>uch process aims at

Z. Jecognition o- haards andpotential haards._. \5aluation o- haards and e6pected

losses.[. \5aluation o- the proposed counter

measures.

*re risk sur5ey should e carriedout to list *re haards. >ite uildingconstruction plant contentsmanagement -actors people -actors *reprotection system post *re acti5ities arethe areas to e co5ered. ighlyvammale material and processessmoke and to6ic gas generation peoplelikely to e azected *re load calculationand speci*c nature o- industry arerele5ant points.

. Fire 'ete&tion and Alar+!"ste+s:

arious types o- detectors area5ailale operating on principles o-

24


25/40

thermal e6pansion thermoelectricsensiti5ity thermo conducti5ity orphotosensiti5ity to detect presence o- smoke increase in temperature lightintensity or total radiation. ,heir typesare 7 ,hermal e6pansion detectorsJadiant energy detectors Light

inter-erence detectors and ionisationdetectors. ,hey should e properlylocated depending upon their range. ,heysimply gi5e alarm and cannot e6tinguish*re. ,hey make us alert -or *re *ghting.

,hough *re detection and alarmsystems are separate systems ut thelatter has to operate Vust a-ter the -ormeroperates there-ore they are consideredtogether. I> _Zb and _Zj] also deal withthem together.

,wo main -unctions o- any *redetection system are

Z. ,o gi5e alarm to start up e6tinguishingprocedure and

_. ,o gi5e early warning to areaoccupants to escape.

It is wrong to speak *re detectors.ctually they detect sensile heat smokedensity or vame radiation to operatee-ore actual *re -ollows. ,heir sensor

detects measurale Xuantity o- theseparameters. decision making de5icecoupled with the sensor compares themeasured Xuantity with a predetermined5alue and when it is dizerent an alarm issounded. detector oth detects andsignals.

uman eing is a good detector as hecan act in a ve6ile way i.e. run awayput out the *re or call the *redepartment. o other detector can workin such selecti5e manner.

>election o- the type o- detector isimportant. For e6ample low risk areasneed thermal detectors a ware housemay ha5e in-rared and ionisationdetectors and a computer area reXuiresionisation or comination detectors.

Location and spacing should edetermined to otain the earliest possilewarning.

>ensiti5ity reliaility maintainailityand staility are important -actors -or

selection.

Fire process has -our stages incipient stage smouldering stage vamestage and heat stage. Uany types o- *redetectors are a5ailale -or 5arioussituations and use-ul at dizerent stageso- a *re (see part _._).

,hermal detectors are o- *6ed

temperature detectors ratecompensatedthermal detectors rate o- rise thermaldetectors line thermal detectors eutecticsalt line thermal detectors and the uldetection system.

>moke detectors are o- photoelectrictype and are o- two classes ,he eamphotoelectric or revected eamphotoelectric detectors.

Flame detectors are o- in-rared (IJ) orultra5iolet() type.

Ionisation (comustion products)detectors are the single chamer or dualchamer ionisation detector and the low5oltage ionisation detector.

Alar+ s"ste+ may e separate torun manually or connected with *redetectors and operale automatically. llworkers must e made aware o- thesound pattern and its meaning. Fire alarmsound should e distinguishale -romother sound in that area. It should eclearly audile to all -acility personnel.

>ound -or eginning o- *re and end o- *reshould e dizerentiated.

.3 Fire !uppression orExtinuis(in !"ste+s :

Uainly three methods are used in allsuch systems 7 (Z) Star0ation or isolationi.e. shutting oz or pre5enting the vow o- -uel and lanketing the *re sur-ace with-orm to seal air5apour mi6ture (_)

Cooling y application o- water -oam ordry chemical powder and ([) S!oteringy applying inert gas (to reduce o6ygen)steam dry chemicals or 5aporising liXuidssuch as `W_ -reon F\ Z[Z methylromide etc.

,wo types o- e6tinguishers are usedportale and *6ed.

.3.1 Porta#le FireExtinuis(ers :

25


26/40

In addition to the *6ed *reinstallations stated in ne6t part portale(*rstaid) *re e6tinguishers are alwaysdesirale -or Xuick manual use on small*res and -or the period till automaticeXuipment or outside *re *ghters work.ll such e6tinguishers should e (Z) o-

reliale make standard and properlyidenti*ed (_) o- right type dependingupon the class o- *re ([) sucient innumer (^) properly located where theyare necessary and readily accessile ()recharged periodically inspected andmaintained in good working condition and() known y the operators who aretrained to use them.

,heir types are 7 (Z) xater type (_)>oda acid type ([) `aron dio6ide type(^) Foam type () ry chemical powdertype and () aporising liXuid type.I>7_Z] is most use-ul -or selectioninstallation and maintenance o- portale*rst aid *re e6tinguishers. etails o- these si6 types are also gi5en in I>7]^_[^ ][^ _jbj ][[ and _ZbZ. ,ales o- their suitaility according to class o- *reand scale i.e. their range or areaco5erage are also gi5en therein. ased onthem numer o- e6tinguishers can edetermined. Uethods o- their testing and

test -orm are also prescried. Je-er them-or -urther details.>ee ,ale Z[.^ and Z[. -or selection

o- portale e6tinguishers.For small *res mostly portale *re

e6tinguishers are used. ,hey aree6plained elow in rie-7

1. !oda A&id 68ater T"pe7Extinuis(er7

,his e6tinguisher is use-ul -or class *re (wood paper -arics ruish etc.). Itshould not e used on *res o- electricityoil chemical or metal. It is a5ailale inoth the shapescylindrical and conical.Its normal capacity is ] Ltr (weight Z^ 3g)and to e used in a range o- to j mt. Itconsumes within Z to Z. minute. Itshould e checked e5ery [ months.

It is held 5ertically up (not in5erted).y standing ^ to mt. away -rom the *rea-ter opening the plunger it is struck onthe hard sur-ace. small _>W^ (>ulphuric

acid ) ottle reaks and due to its mi6turewith soda icaronate solution `W_

(`aron dio6ide) is generated. Yressure o- `W_ throws water at a distance. Itshandle and ottom are held y twohands and water is sprayed on *re toe6tinguish it.

. Foa+ Extinuis(er 7

It is used on class small *res. Itshould not e used on electrical or metal*re. It is a5ailale in ] Ltr cylinder andused in ^ to mt range. It consumeswithin Z. minute. It is a5ailale in wheelmounted trolley o- Zj Ltr and Z Ltrcapacity -or longer use. It should echecked e5ery [ months.

y standing [ to ^ mt away -rom the*re the plunger is pulled up and turnedright up to a slot. It is shaked y turningZj twice. ,hen it is held in5erted. ychemical reaction `W_ is generated whichthrows -oam outside. ,he -oam is notthrown directly in *re ut it is thrown onnearer hard sur-ace so that ecause o- striking -urther -oam is generated andspread on urning sur-ace. It stopso6ygen a5ailaility -or urning andcontrols the *re. Foam is ezecti5e up toZ_ ` temperature only.

3. C5 6Co+pressed as 7

Extinuis(er 7It is use-ul on class \ i.e. electrical*re ecause `W_ is nonconducti5e gas. Itcan e used on class and ` *re also asit diminishes o6ygen to control *re. It isnot ad5isale to use it in a closed room asmore `W_ may e inhaled. ,here-ore opendoors and windows e-ore using it in aroom. It should not e used on *res o- metal sodium potassium and metalhydrides.

It is a5ailale in _ kg ^ kg .j kgand __. kg capacities. >mall cylindersha5e handles and ig cylinders ha5ewheels. Its range is Z to Z. mt. `W_pressure is at ^ to b ar. It should echecked e5ery three months.

/. 'r" C(e+i&al Po=der 6'CP7Extinuis(er 7

,his can e used on any class o- *re. ,here-ore it is known as uni0ersal typeextinguiser . It is generally used on *re

o- vammale liXuid. It is not ezecti5e on*re o- enene ether \W and `>_. For

26


27/40

metal *re special powder e6tinguishersare a5ailale. Z_ and Z kge6tinguishers in cylinders and j kg inwheel models are a5ailale.

Z kg cylinder is consumed withinZ_ to Z seconds and its range is [ to mt. j kg cylinder is consumed within Z

to Z. minute and its range is to j mt.oth should e checked at [ monthsinter5al.

y standing to j mt near the *rethe cylinder is shacked twice y turningZj a sa-ety clip is remo5ed and plungeris pressed or struck so that `W_ ottlereaks and it throws dry chemicals out.

,he dry powder lankets the urningsur-ace stops W_ contact and `W_ comingout also diminishes W_ proportion.

,here-ore *re is controlled y douleaction. Its long nole should e turned inwind direction like a room.

;. Halon Gas Extinuis(er 6HalonAlternati9es77alon Z_ZZ or Z[Z a liXuid gas is

*lled in e6tinguishers. It is used in placeo- `W_ e6tinguishers ut is lighter incomparison. Z. [ and kg cylindersand igger sies are a5ailale in wheelmounted model. y pressing a kno in

capassemly it can e started. oseshould e co5ered to a5oid directinhalation.

It is suitale -or class and ` *res.>ee I> ZZZj -or alon Z_ZZ.

alon is a -ast e6tinguishingagent. It is ideal -or intense and rapid*res. It is nonconducti5e and lea5es notraces when applied. ,here-ore it is alsosuitale -or electrical *res computerrooms etc.

alon interrupts the chain reactionat the vame one o- *re. It is two timesas ezecti5e as `W_ on a weight asis and*5e times as ezecti5e as `W_ on 5olumeasis.

alon is stored under pressure ina cylinder. sXueee grip type nole ispro5ided on top o- the cylinder 5al5edepending upon capacity. It is a5ailale in_ ^ _ and kg capacities. Uostlytwo types o- alons (halogenated agents)are used as they are less to6ic ~ (Z) alon

Z_ZZromochloro divuromethane i.e.

`F_r`l and (_) alon Z[Z ~romotrivuromethane `F[r.

.3. Fixed Fire )nstallations :

Fi6ed automatic *re installations aredesirale -rom the design stage as they

are more ezecti5e than the portale type.

1. Fire H"drants are economical andshould e installed -reely around theplant. ,hey should e kept accessileunostructed and protected -or sa-ety.Indicator posts are ad5isale.

Fire hydrants hoses noles andcouplers are part o- the system. Fi6ednoles are single or doule headed.Uonitor noles are on swi5el Voint andcan e turned as desired and to clear anyostruction. ose noles can ee6tended and laid (i.e. more ve6ile)where5er reXuired. ,hey are o- *6ed vowtype adVustale vow (5ariale discharge)type and a comination type.

,he numer o- hydrants neededdepends on the *re e6posure and thehoselaying distance to the uiltup areas.

,he discharge ports should e at least Zjinch (^ cm) ao5e the ground le5el.

Fire Hose and No22les o- standard

sie doule Vacketed ruerlined shoulde stored in hose o6es and should esuVected to a -ull pressure test once ayear. >pace around hose lines and control5al5es should e clear. isles and doorways should e wide enough and clear toallow rapid use o- hose reel cart or moileeXuipment.

onitor No22les are used in yardsand large congested areas where it isdicult to lay hose line in an emergency.

,he nole is so positioned to direct ahigh pressure water stream o5er desiredarea and height.

8ater Tans are necessary -or thesupply o- *re water at good pressure and5olume. ,hey should not e used -orother purposes such as processreXuirement. I- the tank is commonsuction pipe (its ottom end) -or processwater should e at a higher le5el than thesuction pipe -or *re water into the ottomo- the tank to maintain the le5el o-

reser5ed water -or *re protection.

27


28/40

8ater !uppl" -rom reliale sourcesis essential. Jeser5oirs o5erhead tankspressure tanks pumps pipes andconnections must e maintained well.Flow discharge may 5ary -rom Z to ^litres per second and pressure -rom b toZ kg.fcm_.

TAC uidelines6rules7 for =atersuppl" for ("drants are as under :

xater -or the hydrant ser5ice shall estored in any easily accessile sur-ace orunderground lined reser5oir or ao5eground tanks o- steel concrete ormasonry. ,he ezecti5e capacity o- thereser5oir(ao5e the le5el o- the -oot 5al5eseat in case o- negati5e suction and

ao5e the le5el o- the top o- the pumpcasing in case o- positi5e suction) -or the5arious classes o- occupancies (as perrule b._) and sie o- hydrant installationsshall e as indicated in ,ale Z[.hereunder 7

ote Z7Jeser5oirs o- and o5er __litres capacity shall e in twointerconnected compartments to

-acilitate cleaning and repairs.

ote _7Large natural reser5oirs ha5ingwater capacity e6ceeding tentimes the aggregate waterreXuirements o- all the *re pumpdrawing there-rom may e le-tunlined.

Ta#le 13. : àpacity o- waterstorageNature of Ris Capa&it" of stati&

storae ex&lusi9el"

reser9ed for("drant ser9i&e

Z. Light aard ot less than Z hoursaggregate pumpingcapacity with aminimum o- Z[litres.

_. Wrdinaryaard

ot less than _ hoursaggregate pumpingcapacity.

[. igh aard()

ot less than [ hoursaggregate pumpingcapacity.

^. igh aard()

ot less than ^ hoursaggregate pumpingcapacity.

..Z 7 ,he capacity o- the reser5oir -orWrdinary and igh aard `lassWccupancies may at the

discretion o- the òmmittee ereduced y _ hours invow -rom areliale source (other than atowns main) ut in no case shallthe reser5oir capacity e less than o- that mentioned ao5e.

.._ 7 In case o- Light aard `lassWccupancies the minimumcapacity o- the reser5oir shall eincreased to __ litres i- thehighest voor o- the uilding ismore than Z mt. ao5e thesurroundings ground le5el.

,he capacity -or hydrant ser5ice shalle determined y the class o- occupancyand sie o- installation as per ,ale Z[.b.

Ta#le 13.:Yump àpacity and eli5eryYressure 7

!r.No.

Nature of Ris

Nu+#er of H"drants

Pu+pCapa&it

" inLitres@!e&

6+3@(our7

'eli9er"pressur

e atrated

&apa&it"@&+

Z. Lighthaard

i) ote6ceeding_ii)\6ceeding_ ut note6ceedingiii)\6ceeding ut note6ceedingZi5)\6ceedingZ

_b(])

[j(Z[b)

^b(ZbZ)

^b(ZbZ) plus^b(ZbZ) -ore5eryadditional Z_hydrants orpartthereo- .

.

b

b

bfj.j

28


29/40

.. 7 ,he total pumping capacity need not egreater than Z](j[) irrespecti5e o- thenumer o- hydrant points_. Wrdinar

yaard

i) ote6ceeding_ii) \6ceeding_ ut not

e6ceedingiii)\6ceeding ut note6ceedingZi5)\6ceedingZ

[j(Z[b)

^b(ZbZ)

b(_b[)

b(_b[) plusb(_b[) -ore5eryadditional Z_

hydrants orpartthereo-

b

b

b

bfj.j

.. 7,he total pumping capacity need not egreater than [_(Z]_) irrespecti5e o- thenumer o- hydrant points.[. igh

aard()

i) ote6ceeding_ii) \6ceeding_ ut note6ceedingiii)\6ceeding ut note6ceedingZi5)\6ceedingZ

^b(ZbZ)

b(_b[)

ZZ^(^Z)

ZZ^(^Z) plusZZ^(^Z) -ore5eryadditional Zhydrants or

partthereo- .

b

bfj.j

bfj.j

bfj.jfZ.

^. ighaard()

i) ote6ceeding_ii) \6ceeding_ ut note6ceedingiii)\6ceeding ut not

e6ceedingZ

,wo o- ^b(ZbZ)

,wo o- b(_b[)

,wo o- ZZ^(^Z)

,wo o- ZZ^

b

bfj.j

bfj.j

bfj.jfZ.

i5)\6ceedingZ

(^Z)plusone o- ZZ^(^Z)-ore5eryadditio

nal _hydrants orpartthereo- .

,his pro5ision will apply only in caseswhere the hydrant ser5ice has eenhydraulically designed as per [() ufr b..Z.

ote 7 In case o- Light aardWccupancies the pump deli5erypressure will need to e b kgfcm_ i- the highest voor o- the risk is at aheight e6ceeding Z mt ao5e thesurrounding ground le5el.

Yroper drainage -acility shall epro5ided to drain the *re*ghting waterout o- the asement.

!torae of +aterial in the openshall e protected as under 7

Uetals Uetallicgoods Uachineryand other nonhaardous storage

Wne single hydrant -ore5ery m. o- thestorage peripherylocated eyond _ m. utwithin Z m. o- storagearea.

`oal or ̀ oke Wne single hydrant -ore5ery ^ m. o- thestorage peripherylocated eyond _ m. utwithin Z m. o- storagearea.

Wther >torage Wne doule hydrant -ore5ery ^ m. o- thestorage peripherylocated eyond _ m. utwithin __. m. o- storagearea.

ote Z 7In case o- open storage areas o- -ollowing materials at least o- hydrants shall e replaced y*6ed monitors ha5ing nole oreo- [j mm diameter i- the

indi5idual stack height is more

29


30/40

than m. and total storagee6ceeds tonnes.amoo agasse.+rassfay ,imer.

ote _ 7 xhere hydrantsfmonitors locatedalong one longer side o- a storage

area are more than ] m. -romthose along the other longer sidesuch a storage area shall not edeemed to e protected.

Prote&tion for&o+#usti#le@Ba++a#le liuid!torae Tans :

,ank lessthan _ m. indiameter

Wne doule headed pre-eralytwo single headed hydrantslocated eyond Z m. ut

within [m. o- tank shell. ,anks o5er _m. indiameter

,wo doule headed or -oursingle headed hydrants locatedeyond Z m. ut within [ m.o- tank shell.

ote Z7 In case tanks are located morethan __. m. -rom the dyke wallsone doule hydrant or two singlehydrants shall e replaced ya [j mm monitor.

ote _7xhere the distance o- tank -romthe monitor e6ceeds ^ m. inaddition to pro5isions o- ote Zthe tank shall e protected yFi6ed Foam or Uedium elocityxater >pray >ystem ha5ing priorappro5al o- the `ommittee.

ote [7ydrantsfUonitors shall not einstalled within dyked enclosuresnor can the hydrant main passthrough it.

ote ^ 7 Fi6ed roo- type storage tanksvoating roo- type storage tankse6ceeding [ m. in diameter andulletsf>pheres containingproducts ha5ing vashpoint elow[_ ` shall e protected yUedium elocity xater >pray>ystem con-orming to rele5antregulations.

owe5er manuallyoperated systemsshall also e acceptale.

xater spray systems shall not einsisted -or Insulated 5esselsf>pheres.}

xater spray protection -or small sietanks up to Z mtr diameters in ordinaryand high haard risks shall not e insistedupon.}

. Auto+ati& 8ater !prinlers are o- si6 types. xet pipe dry pipe preactiondeluge comined dry pipe and preactionand sprinklers -or limited water supplysystem. utomatic alarms operated ythe vow o- water should e a part o- sprinkler installation. >uch an alarm maye connected to a central *re station. ,hesprinklers should e regularly checked toa5oid their -ailure to work.

utomatic sprinklers are mostecient and widely used. It reducesinsurance premium consideraly.

Its asic -unction is to spray waterautomatically to a *re the system canalso work as a *re alarm. ,his can edone y installing an electrical water vowalarm switch in each main riser pipe.

>prinklers should e selected on theasis o- temperature rating andoccupancy. ,heir types are \ither heatelement or chemical melts or e6pands toopen the sprinkler. ormal detector

setting is j

`. >prinklers heads normallyco5er Z_ m[ per head. mount o- waterreXuired depends on risk protected vowrange eing .^ to .Z^ lfm_.

In delue s"ste+ water is admittedto sprinklers that are open at all times.eluge 5al5es (water supply 5al5es) cane operated manually or automatically yan automatic detection system.

Documents

13. CHAPTER - 13 Fire and Explosion