COMPARISON OF SPRINKLER DESIGN CRITERIA

1. SPRINKLER INSTALLATION

NFPA 13

Sprinklers are needed wherever there are combustible materials either in the building construction or in its contents, including

the following locations;

a. in noncombustible buildings wherever contents are combustible, including areas where flammable liquids are stored or used.

b. throughout all buildings of combustible construction or those having appreciable amounts of combustible componenets.

c. as the basic protection at hazardous processes such as those involving flammable liquids, even though protected with fixed

extinguishing system.

d. in concealed spaces of combustible construction such as floors, roofs and low attics except where the ceiling is attached

directly to the underside of the supporting beams of a combustible roof or floor and fire stopping is provided.

e. in vacant spaces under the first story of building with combustible floors and under the combustible floors of exterior docks,

platform and piers

f. under roofs over outside loading platforms or docks and under other exterior canopies except where construction is

noncombustible and the area under the canopy is not used for storage

g. in enclosed equipment such as ovens, dryers, dust collectors, large ducts, spray booths, paper machine hoods, paper

machine economizers, part of textile preparatory machines and similar enclosures where combustible materials are processed

or combustible wastes or deposits may accumulate

h. in small enclosed structures such as a penthouses, stairways, passageways, small offices, stockrooms, closets or similar

enclosures of combustible construction or containing combustible material.

i. in elevator towers, including in and under penthouses and in elevator machine rooms.

j. under cutting tables regardless of with and under ducts and storage shelves including slatted decks that are over 4ft (1.20m)

wide, where there are combustible beneath. Sprinklers are needed under ducts of less width if distribution from ceiling

sprinklers is obstructed.

k. at exposed steelwork supporting process equipment such as large tanks, stills, pipelines or equipment containing flammable

chemicals or liquids so constructed or located that the steel would not be well protected by the usual installation of

building sprinklers

l. where combustible storage or construction is introduced in areas where buildings and contents are otherwise noncombustible

m. telephone equipment rooms

BS EN 12845

where a building is to be protected, all areas of that building or of a communicating building shall be sprinkler protected

except in some cases indicated

sprimkler protection shall be considered in the following cases, but may be omitted after due consideration of the fire load in

each cases;

a. washrooms and toilets (but not cloakroom) of non combustible materials and which are not used to store combustible mat'ls

b. enclosed staircases and enclosed vertical shafts (i.e lift or service shafts) containing no combustible material and construc-

ted as a fire resistant separation

c. rooms protected by other automatic extinguishing systems (i.e gas, powder and water spray)

d. wet processes such as the wet end of paper making machines

sprinkler protection shall not be provided in the following areas of a building or plant;

a. silos or bins containing substances which expand on contact with water

b. in the vicinity of industrial furnaces or kilns, salt baths, smelting ladles or similar equipment if the hazard would be increased

by the use of water in extinguishing a fire

c. areas, rooms or places where water discharge might present a hazard. In these cases other automatic extinguishing system

should be considered(i.e gas or powder)

the separation between a sprinkler protected area and a non protected area shall have a fire resistance specified by the

authority but in no case less than 60 minutes. Door shall be self closing or be closed automatically in case of fire.

2.. SPRINKLER SYSTEM TYPES

NFPA 13

Antifreeze sprinkler system - a wet pipe sprinkler system employing automatic sprinklers that are attached to a piping system

that contains an antifreeze solution and that are connected to a water supply. The antifreeze solution is discharged followed

by water, immediately upon operation of sprinklers opened by heat from a fire.

Circulating closed looped sprinkler system - a wet pipe sprinkler system having non-fire protection coonections to auto-

matic sprinkler systems in a closed looped piping arrangement for the purpose of utilizing sprinkler piping to conduct water for

heating or cooling, where water is not removed or used from the system but only circulated through the piping system.

Combined dry pipe - preaction sprinkler system - a sprinkler system employing automatic sprinklers attached to a piping

system containing air under pressure with a supplemental detection system installed in the same area as the sprinklers.

operation of the detection system actuates tripping devices that open dry pipe valves simultaneously and withot loss of air

pressure in the system. Operation of the detection system also opens listed air exhaust valves at the end of feed main which

usually precedes the opening of sprinklers. The detection system also serves as an automatic fire alarm system.

Deluge sprinkler system - a sprinkler system employing open sprinklers that are attached to a piping system that is connected

to a water supply through a valve that is opened by the operation of a detection system installed in the same area as the

sprinklers. When the valve opens, water flows into the piping system and discharges from all sprinklers attached thereto.

Dry pipe sprinkler system - a sprinkler system employing automatic sprinklers that are attached to a piping system containing

air or nitrogen under pressure, the release of which permits the water pressure to open a valve known as a dry pipe valve and

the water then flows into the piping system and out of the opened sprinklers.

Gridded sprinkler system - a sprinkler system in which parallel cross mains are connected by multiple branch lines. An

operating sprinkler will receive water from both ends of its branchline while other branch line help transfer water between

crossmains.

Looped sprinkler system - a sprinkler system in which multiple crossmains are tied together so as to provide more than one

path for water to flow to an operating sprinkler and branchline that are not tied together

Preaction sprinkler system - a sprinkler system employing automatic sprinklers that are attached to a piping system that

contains air that might or might not be under pressure, with a supplemental detection system installed in the same area as the

sprinklers

Wet pipe sprinkler system - a sprinkler system employing automatic sprinklers attached to piping system containing water and

connected to water supply so that water discharges immediately from sprinklers opened by heat from a fire

BS EN 12845

Wet pipe are installation that are permanently charged with water under pressure. Wet pipe installation shall be installed only

in premises where there is no possibility of frost damaged to the installation and where the ambient temperature will not

exceed 95 deg C. Installation subject to freezing may be protected by anti-freeze liquid or trace heating.

Dry pipe are installation that are normally charged with air or inert gas under pressure downstream of dry alarm valve and

water under pressure upstream of the dry alarm valve. A permanent air/inert gas supply to maintain the pressure in the pipe-

work shall be installed. The installation shall be pressurized to fall within the pressure range recommended by the alarm valve

supplier.

Alternate installation incorporate either and alternate alarm valve or a composite set comprising a wet alarm valve and a dry

alarm valve. During winter

Pre-action installations shall be one of the following types;

Type A pre-action installation is normal dry pipe installation in which the control valve set is activated by automatic fire

detection system but not by the operation of the sprinklers. The gas/inert gas pressure in the installation shall be monitored at

all times. A t least one quick opening manually operated valve shall be installed in an appropriate position to enable the

pre-action valve to be activated in an emergency.

Type B installation is otherwise normal dry pipe installation in which the control valve set is activated either by an automatic

fire detection system or by the operation of the sprinklers. Independently of the response of the detectors, a pressure drop

in the pipework causes the opening of the alarm valve. Type B pre-action installation may be installed wherever a dry pipe is

called for and the spread of fire is expected to be rapid. They may also be used instead of ordinary dry pipe systems with or

without an accelarator or exhauster

Where a sprinkler system includes more than one pre-action sprinkler installation, a risk assessment shall be undertaken to

establish wether simultaneous operation of more than one pre-action installation could occur. Where simultaneous charging

of pre-action sprinkler installations may occur, the following shall be implemented

a) the volume of stored water supplies shall be increased by the volume of the pre-action installations

b) the time between multiple pre-action installations tripping and water discharging from any remote test valve on the installa-

tions under consideration shall not exceed 60 sec.

3. CLASSIFICATION OF OCCUPANCYClassification of occupancy relate to sprinkler installation and their water supply.

These occupancy classification should be used to develop criteria for maximum allowable

sprinkler spacing.

NFPA 13 BS EN 12845

Light hazard occupancies Light hazard occupancies

occupancies or portion of other occupancies where the qty schools and other educational institutions

and/or combustibility contents is low and fires with prison

relatively low rate of heat release are expected. Light hazard offices (with no single compartment greater than 126m2 with a fire

occupancies includes occupancies having similar to: resistance of at least 30 min)

churches Ordinary hazard 1 occupancies

club cement works

eaves and overhang sheet metal product factories

educational hospitals

hospitals hotels

institutional libraries (excluding bookstores)

libraries, except large stack rooms restaurants

museums schools

nursing or convalescent room offices

office including data processing data processing (computer room excluding tape storage)

residential

restaurant seating area

theater and auditorium Ordinary hazard 2 occupancies

unused attic photographic film factories

metal working

abattoirs,meat factories

bakeries

biscuit factories

NFPA 13 BS EN 12845Ordinary hazard grp-1 occupancies

occupancies or portions of other occupancies where com- breweries

bustibility is low, quantity of combustible is moderate, chocolate factories

stockpiles of combustibles do not exceed 2.40m high and confectionery

fires with moderate rates of heat release are expected. dairies factories

Ordinary hazard grp-1 occupancies include occupancies laboratories (physical)

having conditions similar to: laundries

car parks

automobile parking and showrooms museums

bakeries and beverage naufacturing leather goods factories

canneries

dairy products manufacturing and processing

electronic plants Ordinary hazard 3 occupancies

glass and glass product manufacturing glass factories

laundries dyers work

restaurant service areas soap factories

photographic laboratories

Ordinary hazard grp-2 occupancies paint application shops with water based paint

occupancies or portion of occupancies where quantity and electronics factories

combustibility is moderate to high. Stockpiles do not exceed radio equipment factories

3.70m high and fire with moderate to high rates of heat washing machine factories

release are expected. Ordinary hazard grp-2 occupancies car workshops

includes occupancies having conditions similar to: animal fodder factories

corn mills

cereal mills sugar factories

chemical plants-ordinary dehydrated vegetable and soup factories

confectionary products broadcasting studios

distilleries railway stations

dry cleaners plant (technical) room

feed mills farm building

horse stables book binding factories

leather goods manufacturing cardboard factories

NFPA 13 BS EN 12845

libraries-large stackroom areas paper factories

machine shops shopping centre

metal working carpet factories (excluding rubber and foam plastics)

mercantile fibre board factories

paper and pulp mills footwear factories (excluding plastics and rubber)

paper process plants knitting factories

pier and wharves linen factories

post office mattress factories (excluding foam plastics)

printing and publishing sewing factories

repair garages weaving mills

stages woolen and worsted mills

textile manufacturing woodworking factories

tire manufacturing furniture factories (without foam, plastics)

tobacco product manufacturing furniture showrooms

wood machining upholstery (without foam and plastics) factories

wood product assembly

Extra hazard grp-1 occupancies High hazard Process occupancies (HHP1)

these occupancies includes occupancies similar to:

upholstering with plastic foam floor cloth and linoleum manufacture

aircraft hangar resin, lamp black and turpentine manufacture

combustible hydraulic fluid use area rubber substitute manufacture

die casting wood wool manufacture

metal extruding paint application shops with solvent

plywood and particle board manufacturing refrigerator factories

printing printing works

rubber reclaiming cable factories for PP/PE/PS or similar burning characteristics other

saw mills than Ordinary hazard 3 (OH3)

textile picking injection moulding (plastics) for PP/PE/PS or similar burning charac-

burlap teristics other than ordinary hazard 3 (OH3)

NFPA 13 BS EN 12845

Extra hazard grp-2 occupancies rubber good factories

these occupancies includes occupancies similar to: synthetic fibre factories (excluding acrylic)

rope factories

asphalt saturating carpet factories including unexpanded plastics

flammable liquid spraying footwear factories including plastics and rubber

flow coating

manufactured home

open oil quenching High hazard Process occupancies (HHP2)

plastic processing

solvent cleaning fire lighter manufacture

varnish and paint dipping tar distilling

depots for buses, un-laden lorries and railway carriages

candle wax and paraffin manufacturers

paper machine halls

carpet factories including rubber and foam plastics

saw mill

chipboard manufacturing (1)

paint, colour and varnish manufacture

High hazard Process occupancies (HHP3)

cellulose nitrate manufacture

rubber tires for cars and lorries

manufacture of material factor M3 (material which are predominant-

ly unexpanded plastic) foam plastics, foam rubber and

rubber goods

High hazard Process occupancies (HHP4)

firework manufacture

4. SPRINKLER SPACING AND PROTECTION AREAS

NFPA 13protection areas and maximum spacing of standard spray pendent and upright sprinklers

protec- spacing protec- spacing protec- spacing protec- spacing

tion area max. tion area max. tion area max. tion area max.

construction type m2 m m2 m m2 m m2 m

non combustible

obstructed and

unobstructed and

combustible un-

obstructed 20.9 4.5 12.1 4.5 9.3 3.6 9.3 3.6

combustible

obstructed 15.6 4.5 12.1 4.5 9.3 3.6 9.3 3.6

protection areas and maximum spacing of standard sidewall spray sprinklers

max.distance along the wall(S)

max.room width (L)

max.protection area

combustible finish non combustible or limited

ordinary hazardlight hazard

or limited combustible fin.

combustible finish non combustible or limited

or limited combustible fin.

light hazard ordinary hazard extra hazard high piled storage

3

3

7.4

3

3

9.3

4.26

3.65

11.15

4.26

3.65

18.2

protection areas and maximum spacing of extended coverage spray pendent and upright sprinklers

protec- spacing protec- spacing protec- spacing protec- spacing

tion area max. tion area max. tion area max. tion area max.

construction type m2 m m2 m m2 m m2 m

37.18 6

30 5.48

37.18 6 23.98 4.87

30 5.48 18.21 4.26 18.21 4.26 18.21 4.26

unobstructed 23.98 4.87 13.38 3.65 13.38 3.65 13.38 3.65

37.18 6

obstructed non- 30 5.48

combustible(when 37.18 6 23.98 4.87

specifically listed 30 5.48 18.21 4.26 18.21 4.26 18.21 4.26

for such use) 23.98 4.87 13.38 3.65 13.38 3.65 13.38 3.65

obstructed combus-

ble N/A N/A N/A N/A N/A N/A N/A N/A

protection areas and maximum spacing of extended coverage sidewall spray sprinklers

unobstructed, smooth, flat

light hazard ordinary hazard extra hazard high piled storage

7.3

light hazard

spacing (ft)

ordinary hazard

protection area (m2) spacing (ft)

37.18

protection area (m2)construction type

8.5 37.18

BS EN 12845

maximum coverage and spacing for sidewall sprinklers

hazard max. area room room rows of spacing

class per sprin- between width,w length, l sidewall pattern

kler (m2) sprinklers sprinklers

(m) (m) (m)

W≤3.7 any 1 single line

3.7< w≤7.4 ≤9.2 2 standard

3.7< w≤7.4 ≤9.2 2 standard

LH 17 4.6 w>7.4 any 2 staggered

W≤3.7 any 1 single line

3.7< w≤7.4 ≤6.8 2 standard

3.7< w≤7.4 ≤6.8 2 staggered

OH 9 3.4 w>7.4 any 2 standard

hazard class max. area/sprinkler

maximum coverage and spacing for sprinkler other than sidewall

m2 standard layout staggered layout

maximum distances, m

21 4.6 4.6LH

OH

HHP

12 4 4.6

9 3.7 3.7

2.3

spacing along walls

sprinklers

to end of

wall (m)

1.8

5. WATER DEMAND REQUIREMENT AND TANK CAPACITY

NFPA 13Used in Pipe schedule method

Water supply requirement for Pipe schedule sprinkler system

occupancy min. residual acceptable flow duration in min. tank size

classification pressure req'd at base of riser minutes ft3 (m3)

light hazard 15 psi (1.034 bar) 500-750 gpm 30-60 min 2010 (57)

ordinary hazard 20 psi (1.38 bar) 850- 1500 gpm 60-90 min 6809 (193)

Used in Hydraulic Calculation method (values shall be added to the sprinkler water demand)

Hose stream demand and water supply duration requirement

occupancy Inside hose total duration in

classification (gpm) minutes

light hazard 0,50,100 100 30

ordinary hazard 0,50,100 250 60

extra hazard 0,50,100 500 90

BS EN 12845

Pressure and flow requirements for pre-calculated LH and OH systems

hazard flow pressure at the max. demand pressure at the

class (lpm) control valve set flow (lpm) control valve set

(bar) (bar)

LH

(wet &preaction) 225 2.2+ p s ………..

OH1

(wet &preaction) 375 1.0+ p s 540

OH1

(dry&alternate)

OH2

(wet &preaction) 725 1.4+ p s 1000

OH2

(dry&alternate)

OH3

(wet &preaction) 1100 1.7+ p s 1350

OH3

(dry&alternate)

OH4

(wet &preaction) 1800 2.0+ p s 2100 1.5+ p s

notes;

p s = is the static head loss due to the height of the highest sprinkler in the array concerned above the control valve set, in bar

LH water duration is 30 min.

OH water duration is 60 min.

HHP water duration is 90 min

0.7+ p s

…………

1.0+ p s

1.4+ p s

BS EN 12845

minimum effective capacity of reduced capacity tanks

hazard class minimum effective capacity, m3

LH (wet or pre-action) 5

OH1 (wet or pre-action) 10

OH1 (dry or alternate) 20

OH2 (wet or pre-action) 20

OH2 (dry or alternate) 30

OH3 (wet or pre -action) 30

OH3 (dry or alternate) 50

OH4 (wet or pre -action) 50

HHP and HHS 70, but in no case less than 10% of the full capacity

the following conditions shall be met for reduced capacity tanks;

1. the inflow shall be from a town main and shall be automatic, via at least two (20) mechanical float valves

the inflow shall not adversely influence the pump suction. The failure of a single float valve shall not impair the required infill rate

2. the effective capacity of the tank shall be no less than the figure above

3. the tank capacity plus the inflow shall be sufficient to supply the system at full capacity

4.it shall be possible to check the capacity of the inflow

5. the inflow arrangement shall be accessible for inspection

6. AREAS OF SPRINKLER OPERATION AND DENSITY

NFPA 13

operation (m2)

139

139

232

occupancy

classification

light hazard

ordinary hazard

extra hazard

areas of sprinkler

4.1

6.1 (ord.haz.1) 8.1 (ord.haz.2)

12.2 (ext. haz 1) 16.3 (ext.haz 2)

density

(l/min)m2

BS EN 12845

hazard design density area of operation (m2)

class mm/min wet or preaction dry or alternate

LH

OH1

OH2

OH3

OH4

HHP1

HHP2

HHP3

HHP4

7. SYSTEM PRESSURE

NFPA 136.90 bar is the minimum system pressure while 12.10 bar is the maximum pressure. 24 bar is the maximum shut off pressure

BS EN 12845Except during testing, water pressure shall not exceed 12 bar at equipment connectios. The pressure in pumped system shall take into

account any increase in driver speed and pressure due to closed valve condition

7.50

90

180

270

not allowed used HHP1

2.25 84

325

325

325

deluge (see note)

10.00

12.50

72

144

216

360

260

260

260

not allowed used OH1

5.00

5.00

5.00

5.00

8. POCKET CEILING AND CONCEALED SPACES PROTECTION

NFPA 13

Sprinklers shall be required In all ceiling pockets. Sprinklers shall not be required in ceiling pockets if all the following are met ;

1. the total volume of the unprotected ceiling pocket does not exceed 1000 ft3 (28.3m3)

2. the depth of the unprotected ceiling pocket does not exceed 36 in. (914mm)

3. the entire floor under the unprotected ceiling pocket is protected by sprinklers at the lower ceiling elevation

4. the total size of all unprotected ceiling pockets in the same compartment within 10 ft (3.0m) of each other does not

exceed 1000ft3 (28.3m3)

5. the unprotested ceiling pocket has non combustible or limited-combustible finishes

6. quick response sprinklers are utilized throughout the compartment

BS EN 12845

1. if the height of the concealed space at roof and floor exceeds 0.80m measured between the underside of the roof and the top

of the suspended ceiling or between the floor and the underside of the rasised floor, these spaces shall be sprinkler protected.

2. if the height of the concealed space at roof and floor is no greater than 0.80m, the spaces shall be sprinkler protected only if they

contain combustible materials or are constructed with combustible materials. Electric cables with voltage less than 250V, single phase

with a maximum of 15 cables per tray are allowed