Design-Of-Water-based-Fire-Fighting-System-converted.pdf

helpful in design calculations

1. Design Criteria for Water Based Fire
Fighting System
1
Prepared by :
Prof. Praveen Patel
Head of the Department
Dept. of Fire Tech. & Safety Engg.
Institute of Engineering & Science IPS Academy, Indore.
1

2. 2
FireandSafetyMeasures:
TheFireandSafetyMeasuresinahighrise
buildingcanbroadlyclassifiedintothetwomajor
categories:
•PreventiveMeasures.
•ProtectiveMeasures.
2

3. 3
(A)PreventiveMeasures:Arethosemeasures
whicharetakencareoffduringdesigningofabuilding
structureanddoesnotneedanyenergyconsumption.
Thesemeasuresaredirectlyaffectthearchitectureand
constructionvalueofthebuilding.Thesesystemare
installedduringthedesignandasapartofthebuilding.
Thebestexampleofthepreventivemeasuresare.
(i)TheFireresistanceofbuildingstructure.
(ii)FireandSmokeventingforsmokeextraction.
(iii)Theinternalmeansofevacuation.
(iv)IsolationfromneighboringStructure.
(v)Accessforoutsideemergencyservices.
(vi)SitePlanning.
(vii)Compartmentationofinternalstructure.
3

4. 4
(B)Fire Protection: Are those measure which are
taken care off during after designing of building structure
and does need energy consumption for activation.
These measure are further classified in a general way
under following heads:
(i)Portable fire extinguishers
(ii)Fixed fire aid fire fighting equipments like hose reels.
(iii)Fire Hydrant Installation.
(iv)Manual/Automatic Fire detection and alarm systems.
(v)Fixed Automatic Fire Fighting systems.
(a)Water Sprinkler system.
(b)CO
2
Fire Fighting System
(c)FM 200 Fire Fighting System
(vi) Mobile Fire Fighting System.
4

5. 5
CodesandlocalByeLaws:
Awidevarietyofrulesandregulationsareexistent
regardingfiresafetyofbuildingsbothnationallyand
internationally.Althoughallcodesandlocalbyelawsin
respectoffiresafetyarebasedonthesametheme,they
differvastlyintheirmethodofapplications.Fire
regulationscanbebroadlydividedinthreecategories
•Mandatory/obligatory
•Recommendatory
5

6. 6
ThecodeofpracticeseriesofBISvideIS1641toIS1648
providessufficientguidelinesonnationalbasis,asgiven
below:
Codeofpracticeforfiresafetyofbuildings(General)
1641-60:Generalprinciplesandfiregrading
1642-60:Materialsanddetailsofconstruction
1643-60:ExposureHazard
1644-60:Personalhazard
1645-60:Chimneys,flues,fluepipesandhearths.
1647-60:Electricalinstallations
1647-60:Non-electriclightingequipmentoilandgas
heatersandburnersofsmallcapacity
1648-61:Firefightingequipmentanditsmaintenance
includingconstructionandinstallationsof
fireproofdoors.
6

7. 7
CLASSIFICTION OF BUILDINGS BASED ON
OCCUPANCY
(As Per National Building Code 1983)
In respect of making passive or active fire fighting provisions,
buildings are classified in following groups:
Residential Educational Institutional Assembly Business
Mercantile Industrial Storage Hazardous
Group Type
A Residential
B Educational
C Institutional
D Assembly
E business
F Mercantile
G Industrial
H Storage
J Hazardous
7

8. 8
GENERAL PRINCIPLES OF FIRE GRADING OF
BUILDINGS
(AbstractsFromIS:1641-1960)
(A)FireHazards
Firesafetyofbuildingsshallbeconsideredfromthree
aspectsandprotectionshallaccordinglybeprovided
againstthefollowingthreetypesoffirehazards:
1.PersonalHazard.
2.InternalHazard.
3.ExposureHazard.
8

9. 9
(a)PersonalHazard:Possibilityofloss-ordamagetolife,
referredtoas'personalhazard’.
Theconsiderationof'personalhazard'isnaturallyof
paramountimportanceandrequirestheprovisionofliberally
designedandsafefireproofexitsorescapesinallbuildings
andparticularlythosehavingmorethanonestorey.
(b)InternalHazard;Possibilityoffireoccurringand
spreadinginsidethebuildingitself,referredtoas'Internal
hazard';and
Internalhazard'concernsdamageordestructionofthe
buildingandinfluelencesdirectly'personalhazard'.The
internalhazardisdirectlyrelatedtothefireloadwhichinturn,
enablesthebuildingtobegradedwhenconsideredalongwith
thedurationofthefire.
9

10. 10
(c)ExposureHazard;Possibilityoffirespreadingfroman
adjoiningbuildingorbuildingsorfromacrossastreetorroad,
referredtoas'exposurehazard'.
'Exposurehazard'dealswiththeriskoffirespreadingintoa
buildingthroughtheopenairfromafireinotherbuildings,
fromstacksofcombustiblematerial,etc;orintoadivisionor
compartmentofabuildingthroughtheopenairfromafirein
otherdivisionorcompartmentofthesamebuilding.Itdoes
notincludetheriskoffireenteringabuilding,divisionor
compartmentdirectlythroughseparatingordiversionwallsor
floorsorthroughverticalshafts,suchasstaircases.
10

11. 11
(B)Fire Load
Fireloadistheamountofheatinkilo-caloriewhichis
liberatedpersquaremetersoffloorareaofa
compartmentbythecombustionofthecontentsofthe
buildingandanycombustiblepartsofthebuilding
itself.Theamountofheatisusedasthebasisfor
gradingofoccupancies.
Thefireloadisdeterminedbymultiplyingtheweightof
allcombustiblematerialsbytheircalorificvaluesand
dividingthefigurebythefloorareaunder
consideration.
11

12. 12
Example:Abuildingorasectioncontainingnno.of
combustiblematerialhavingquantityinkg.q1,q2,q3….qn
&havingcalorificvalve,C1,C2,C3…..uptoCninkcal/kg
overanareaofXm
2
.Thenthefireloadiscalculatedas.
FireLoad=∑q1xC1+q2xC2+…+qn-1xCn-1+qnxCnkcal/m
2
X
Calorificvalue:theamountofheatliberatedwhenthe
unitmassofcombustiblematerialundergoestocomplete
combustion.
12

13. 13
Sr. No. Substance Calorific value. Kcal/kg
1Coal,(Lignite) 291
2Charcoal 7235
3Woodandstraw 4749
4Crudefueloil 10422
5Kerosene 11038
6Coal-taroil 11138
7WaterGases 3536
8Coalgas 4006
9Hydrogen 34136
10Paraffinwax 11256
The calorific value of some common combustible material
are as follows:-
13

14. 14
(C)GradingofOccupancybyFireLoad:
AsforasInternalhazardconcerni.e.possibilityoffire
occurringandspreadinginsidethebuilding.Itisdirectly
relatedtoFireLoad.TheOccupanciesshallbegradedin
tothreeclassesasfollows:
(a)OccupanciesofLowFireLoad.
(b)OccupanciesofModerateFireLoad.
(c)OccupanciesofHighFireLoad.
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15. 15
(a) Occupancies of Low Fire Load:
Thefireloadofanoccupancyshallbedescribedaslowif
itdoesnotexceedanaverageof275000kcal/m
2
ofnet
floorareaofanycompartment,noranaverageof550000
kcal/m
2
onlimitedisolatedareas,providedthatstorageof
combustiblematerialnecessarytotheoccupancymaybe
allowedtoalimitedextentifseparatedfromtheremainder
andenclosedbyfireresistingconstructionofan
appropriategrade.
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16. 16
(b)OccupanciesofModerateFireLoad:
Thefireloadofanoccupancyshallbedescribedas
moderateifitexceedsanaverageof275000kcal/m
2
ofnetfloorareaofanycompartmentbutdoesnot
exceedanaverageof550000kcal/m
2
noranaverage
of1100000kcal/m
2
0nlimitedisolatedareas,provided
thatstorageofcombustiblematerialnecessarytothe
occupancymaybeallowedtoalimitedextentif
separatedfromtheremainderandenclosedbyfire
resistingconstructionofanappropriategrade.
16

17. 17
(c)OccupanciesofHighFireLoad:
Thefireloadofanoccupancyshallbedescribedas
highifitexceedsanaverageof550000kcal/m
2
ofnet
floorareaofanycompartmentbutdoesnotexceedan
averageof1100000kcal/m
2
0fnetfloorarea,noran
averageof2200000kcal/m
2
onlimitedisolatedareas.
17

18. 18
TheTACi.e.TariffAdvisoryCommittee Further
elaborateonthedegreeofhazardinsidetheoccupancy
andclassifiedthedegreeofhazardunderfollowingfour
heads:
▪Lighthazard.
▪OrdinaryHazard
▪HighHazard-A
▪HighHazard-B

19. 19
We can mathematically express the listed degree of hazard in
terms of fire load. If X kcal/m
2
is the Fire load of a net floor Area
than for
Light Hazard the value of X =0 <X <275000 kcal/m
2
Ordinary Hazard the value of X= 275000 < X <550000 kcal/m
2
High Hazard-A the value of X = 550000 < X <1100000 kcal/m
2
High Hazard-B the value of X = 1100000 <X kcal/m
2
19

20. 20
HydrantSystem:-TheHydrantSystemisaSystematic
arrangementofpipeNetworkwithintheoccupancyto
facilitate,forFireFightingoperationwithwaterasan
Extinguishingmedia.
Themajorcomponentofahydrantsystemareasfollows:-
•Staticwatertank/terracetank.
•PumpHouse
•WaterMains.
•Standpost/watermonitors.
•HoseBox.
•Accessories(ControlValve,SluiceValve,NRVetc)
20

21. 21
WaterSupply:
Waterforthehydrantserviceshallbestoredisan
easilyaccessiblesurfaceorundergroundlinedreservoir
orabovegroundtanksofsteel,concreteormasonry.
Theeffectivecapacityofthereservoirabovethelow
waterlevel(definedhereunder),orabovethetopofthe
pumpcasing(incaseoffloodedsuction)ifthesameis
higherthanthelowwaterlevel,forthevariousclassesof
occupanciesandsizeofhydrantinstallationsshallbeas
indicatedintable1.
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22. 22
Nature of Risk Capacity of Static Storage
Exclusively reserved for hydrant
service.
1.Light Hazard
Notlessthan1hour'saggregate
pumpingcapacitywithaminimumof
1,35,000liters.
2. Ordinary Hazard
Not less than 2 hour's aggregate
pumping capacity
3. High Hazard-A
Not less than 3 hour's aggregate
pumping capacity
4. High Hazard-B
Not less than 4 hour's aggregate
pumping capacity
TABLE-1
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23. 23
Example:Ifaoccupancy considerashigh
hazardAandthedischargerequirementfor
thepumpdeliveryis114Liter/sec,thenthe
capacityofstaticwater tankmay be
calculated as:
CapacityofstaticWaterTank=3x114x60x60
Liter
= 12,31,200.
Liter

24. 24
Pumps
Pumps shall be exclusively used for firefighting purposes,
be of a type approved by the Committee, and shall be :-
•Electric Motor or Steam Turbine driven centrifugal pumps.
or
•Compression ignition engine driven centrifugal pumps.
or
•Vertical turbine submersible pumps.
or
•Quadruple acting reciprocating steam pumps.
24

25. 25
Nature of
Risk
Number of
Hydrants
Pump Capacity in
Liters/ Sec.
(M3/hour)
Delivery pressure
at pump
discharge end at
rated capacity in
kg/cm
2
1.Light
hazard
i)Not exceeding 2027 (96) 5.6*
i)Exceeding 20 but
not exceeding 55
38 (137) 7
i)Exceeding 55 but
not exceeding
100
47 (171) 7
i)Exceeding 100 47 (171)
Plus 47 (171)
For every
additional 125
Hydrants or part
thereof.
7/8.8
The size and capacity of pumps may be determine as per the
table given below
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26. 26
Nature of RiskNumber of Hydrants Pump
Capacity in
Liters/ Sec.
(M3/hour)
Delivery
pressure at
pump
discharge end
at rated
capacity in
kg/cm2
2. Ordinary
Hazard
i)Not exceeding 20 38 (137) 7
i)Exceeding 20 but not
exceeding 55
47 (171) 7
i)Exceeding 55 but not
exceeding 100
76 (273) 7
i)Exceeding 100
Plus 76 (273)
For every
additional 125
Hydrants or part thereof.
76 273) 7/8.8
26

27. 27
Nature of
Risk
Number of Hydrants Pump
Capacity in
Liters/ Sec.
(M3/hour)
Delivery
pressure at
pump
discharge end
at rated
capacity in
kg/cm2
3. High
Hazard-A
i)Not exceeding 20 47 (171) 7
i)Exceeding 20 but not
exceeding 55
76 (273) 7/8.8
i)Exceeding 55 but not
exceeding 100
114 (410) 7/8.8
i)Exceeding 100
Plus 114 (410)
For every
additional 150
Hydrants or part thereof.
114(410) 7/8.8/10.5
27

28. 28
Nature of
Risk
Number of Hydrants Pump
Capacity in
Liters/ Sec.
(M3/hour)
Delivery
pressure at
pump
discharge end
at rated
capacity in
kg/cm2
4. High
Hazard (B)
i) Not exceeding 20Two of 47
(171)
7
ii) Exceeding 20 but not
exceeding 55
Two of 76
(273)
7/8.8
iii) Exceeding 55 but not
exceeding 100
Two of 114
(410)
7/8.8
** iv) Exceeding 100
(410) Plus one of 114
(410)
for every additional 200
Hydrants or part thereof.
Two of 114 8.8/10.5
28

29. 29
Example: If a occupancy consider as ordinary
hazard and the discharge and pressure
requirement of pump at delivery side are 2800
lt./mini and 7 kg./cm
2
respectively then the
capacity of pump may be calculate as
capacity of pump = 100 x Q x P Watt
60
where Q is discharge in Ltr./mini.
Pis pressure in kg/cm
2
capacity of pump= 100 x 2800x 7 Watt
60
= 32666 watt
= 32666/ 746= 43.78
~40 HP

30. 30
Types of Pipes Class of
Pipe
I.S. Specification
i)HorizontallyCastIronpipes B IS: 7181
ii)VerticallyCastIronPipes A IS: 1537
Iii)CentrifugallyCast(Spun)Iron
pipes
A IS: 1536
WaterMains:
Thehydrantsmainsshallbenormallylaidundergroundand
shallbeofanyoneofthefollowingtypes:
(a) CastIrondoublesflangedpipesconformingtothefollowing
standards:
(b) Wroughtormildsteelpipes(galvanizedorungalvanized)of
'Medium'gradeconformingtoIS:1239orIS:3589havingwelded
jointsandcoatedandwrappedasperIS:I0221.
(c) UndergroundPVC‘Class4”pipesconformingtoIS:4985
andHDPEpipesconformingtoIS:4984.
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31. 31
Numberofhydrantsin
thewholesystem
Size of
Mainsmm
Percentageofall
mains including
terminalmainsand
risers*.
1to20 100 100%
21to55 125
100
45%
55%
56to100 125
100
60%
40%
TABLE 3 (FOR LIGHT HAZARD OCCUPANCIES)
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32. 32
Number of
hydrantsinthe
wholesystem
SizeofMainsmmPercentageofall
mains including
terminalmainsand
risers*.
1to5 100 100%
6to20 125
100
40%
60%
21to55 150
125
100
20%
35%
45%
56to100 150
125
100
25%
40%
35%
Exceeding100 SeeN.B.3(a)and
3(b)hereunder
TABLE 3A (FOR ORDINARY HAZARD OCCUPANCIES )
32

33. 33
Example:
AOrdinaryhazardoccupancyhavingthedimension
250x350m2havingtotallengthofwatermainsabout
1200m.Initsperiphery.Ifthetotalno.ofhydrant
pointsintheoccupancyare30thenthepercentageof
piping350mcanbecalculateasfollows:
Thelengthofwatermainshavingdia150mm=20%of
the1200mt.=240m.
Thelengthofwatermainshavingdia125mm=35%of
the1200mt.=420m.
Thelengthofwatermainshavingdia100mm=45%of
the1200mt.=540m.

34. 34
HydrantPoints:
Thehydrantpointistheverticalriserhavingelevationof
onemeterfromthegroundlevelwithfemaleinstantaneous
couplinghavingdia63mm.Itisconnectedwiththewater
mains.
Thecalculationofhydrantpointismadeonthebasicof
degreeofhazard.Onceweknowthelengthofwater
mainsinsideoccupancythenfromthemaximumdistance
criteriaweareabletocalculatetheno.ofhydrantpoints
insideoftheoccupancy.
34

35. 35

36. 36
Example:Supposeanoccupancyhavingthelengthof
watermainsisX-meterthentheno.ofhydrantpointsmay
becalculatedasfollows:-
•Incaseoflighthazardno.ofhydrantpoints=X/60
•Incaseofordinaryhazardno.ofhydrantpoints=X/45
•IncaseofHighhazard-Ano.ofhydrantpoints=X/30
•IncaseofHighhazard-Bno.ofhydrantpoints=X/25
Incalculatingthenumberofhydrantsinthesystem,a
doubleheadedhydrantshallbecountedastwo,afixed
monitorof63mmsizehavingnozzleboreof32mmshall
becountedasthreeafixedmonitorof75mmsizehaving
nozzleboreof38mmshallbecountedasfouranda
monitorof100mmsizehavingnozzleboreof45mmassix
hydrantpoints
36

37. 37
37
Risers:
TheRisersaretheverticalpipeworkhavingmain
diaof100mmstartsrisingfromgroundleveltothetop
mostfloorofthebuilding.Thesearethepartofwater
mainsandhavingsamematerialasofthewatermain.
Therisersarefurtherdesignonthebasisof
degreeofhazardaswellasthetypesofoccupancies.
Theminimumdistancebetweentworiserinsidea
buildingshallbe45mincaseoflighthazardandordinary
hazardandforevery30mthereshouldbeoneriserin
caseofhighhazard.
TheRisersarefurtherdividedintofollowingheads.
1.DryRiser.
2.WetRiser
3.WetRisercumDowncomer.

38. 38
38
1.DryRisers:DryRiserareverticalpipeworkhaving
minimumdia100mmconnectedfromwatermainsat
groundleveltothetopmostfloorofthebuilding.
TheseRisersareDryinnormalposition.These
Risersarenormallyinstalledinlighthazard
occupancy/building.

39. 39
39

40. 40
40
2.WetRisers:WetRisersareverticalpipework
havingminimumdia100mmconnectedfromwater
mainsatgroundleveltothegravityPressure.These
Risershave24hrs.watersupplyfortheFireFighting
Operation.Theseriseraremainlyinstalledinmedium
hazardoccupancy.

41. 41
41

42. 42
42
3.WetRiserscumdowncomer:Theseare
verticalpipeworkparalleltobuildingheighthaving
minimumdiaof100mmconnectedfromwatermains
atgroundleveltotheterracetankwithaefficient
capacitypumpattheterracetank.TheseRiserhave
24hrs.watersupplywithaminimumpressureof3
kg/cm
2
insidethebuildingforFireFightingOperation.
TheseRiseraremainlyinstalledinhighhazard
occupancy.

43. 43
43

44. 44
44
InternalHydrant:TheInternalHydrantarethe
pointsgivenbyrisersoneachfloorforFire
Fightingpurpose.Thesepointscomprisesofone
landingvalve,on/twofemaleinstantaneous
couplingsandoneHoseboxhavingtwohose
pipeoflength15m.withtwolongbranchpipe.

45. 45
HoseBox
Thehoseboxcontaintwohosepipeoflength15m.with
63mmdia.Itisalsoequippedwithtwobranchpipe.The
patternofbranchpipedependsuponthelocation.
Normallythelongbranchpipeforstrongjetareplaced
insidethehosebox.
45

46. 46
46
QUESTIONS?

47. 47
47