IS 15105:2021: the sprinkler code, with its hazard classes, head spacing, water storage and maintenance values
Updated By Flamekite Editorial DeskFacts checked against official sources on
Quick answer
IS 15105:2021 is the Indian code of practice for the design, installation and maintenance of fixed automatic sprinkler fire extinguishing systems. It is the first revision, published in July 2021 by the Fire Fighting Sectional Committee, CED 22, and it replaced IS 15105:2002, which BIS withdrew on 14 March 2022.
The values most searched: design density of 2.25, 5 and 12.2 lpm per m2 over 84, 360 and 260 m2 for light, ordinary and high hazard (cl. 8.1); a standard head covering at most 21, 12 and 9 m2 (cl. 9.17.1); and sprinkler water for at least 30, 60 and 120 minutes of pump running (Table 30). For most building types, the building code's own table sets water and pumps instead (cl. 1.6). No Quality Control Order makes the code or sprinkler heads compulsory to certify.
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IS 15105:2021 at a glance: 12 facts
| What | The rule | Source |
|---|---|---|
| Title | Design, Installation and Maintenance of Fixed Automatic Sprinkler Fire Extinguishing Systems, Code of Practice | BIS, IS 15105:2021 |
| Edition | First revision, July 2021; first published in 2002 with pre-calculated systems only. The revision keeps pre-calculated sizing for small systems, requires hydraulic calculation for high hazard, adds high-rise rules (Annex B, 45 m per installation), wider storage classes and ESFR and large drop heads (foreword) | BIS, IS 15105:2021 |
| Committee | Fire Fighting Sectional Committee, CED 22, of the Civil Engineering Division | BIS, IS 15105:2021 |
| Replaces | IS 15105:2002, withdrawn on 14 March 2022 | BIS standards database |
| Scope | Design, installation and maintenance of sprinkler systems in buildings including industrial and storage, and any later addition or repair (cl. 1.1, 1.3) | BIS, IS 15105:2021 |
| Not covered | Water spray and deluge systems (IS 15325, IS 15519), and ships, aircraft, vehicles and mines (cl. 1.4, 1.5) | BIS, IS 15105:2021 |
| Building groups A to F | Water and pumping capacity come from Table 7 of SP 7 (Part 4); the code's own pump and water clauses apply only to occupancies that table does not cover (cl. 1.6) | BIS, IS 15105:2021 |
| Hazard classes | Light, ordinary (moderate), high, and storage (cl. 5.1) | BIS, IS 15105:2021 |
| Maximum pressure | 7 bar in the installation (cl. 10.3.3) | BIS, IS 15105:2021 |
| Pre-calculated pipe sizing | Allowed only for light and ordinary hazard with 5,000 m2 or less of floor area, and not for gridded or looped layouts (cl. 10.3.1) | BIS, IS 15105:2021 |
| Compulsory BIS mark | None for the code; sprinkler heads (IS 9972) had only a draft order on 24 October 2026 | BIS compulsory list |
| Where it is named | Fire rules and NOC conditions that cite it, such as Maharashtra's Note 21(a), use the code for sprinkler design; the code itself binds only through such a rule or contract | BIS standards database |
IS 15105:2021 and the standards beside it: who covers what
| Option | Type | What it covers | Its role next to IS 15105:2021 | Source |
|---|---|---|---|---|
| IS 15105:2021 | Code of practice | Design, installation and maintenance of the sprinkler system | The sprinkler design and upkeep code | BIS, IS 15105:2021 |
| SP 7 (Part 4) | Building code part | Fire and life safety; Table 7 sets water and pump capacity for building groups A to F | Prevails for those groups over cl. 12 and 13 of IS 15105 (cl. 1.6) | BIS, IS 15105:2021 |
| IS 9972:2023 | Product standard | Sprinkler heads | The heads that IS 15105 places; no compulsory mark yet | BIS standards database |
| IS 15325 and IS 15519 | Design standards | Water spray and deluge systems | Not covered by IS 15105; high-hazard areas may need them (cl. 1.4, 5.4.2) | BIS, IS 15105:2021 |
| IS 13039:2014 | Design standard | External hydrant systems | Where a hydrant system backs the sprinklers, its reservoir rules apply to combined tanks (cl. 13.1, 13.3) | BIS, IS 15105:2021 |
| IS 2189:2026 | Code of practice | Detection and alarm | Detection is no substitute for sprinklers; see /is-codes/is-2189 | BIS, IS 15105:2021 |
How to check a sprinkler system against IS 15105:2021: 6 steps
Name the edition
Write IS 15105:2021 on the drawing, AMC and audit report; the 2002 edition was withdrawn on 14 March 2022.
Fix the hazard class
Check each area against cl. 5 and the 126 m2 light hazard compartment limit, and note any storage above the heights in Table 6.
Check design values
Match density and area of operation to cl. 8.1, and head area and spacing to cl. 9.17 (21, 12 or 9 m2; 4.5 or 3.75 m).
Check the water
Confirm tank and pumps against SP 7 (Part 4) Table 7 first, otherwise Tables 29 and 30, with the 20 percent pump margin (cl. 12.1).
Check pipes and pressure
Pipe sizing method per cl. 10.3, maximum pressure 7 bar, velocity at most 6 and 10 m/s.
Check records
Daily pump runs, weekly gauge log, 6-monthly head inspection and discharge test, yearly flushing, and 2-yearly tank cleaning (cl. 15.6).
IS 15105 design density and area of operation by hazard
Clause 8.1 sets the minimum water density and the largest area assumed to operate at once: 2.25 lpm/m2 over 84 m2 for light hazard, 5 over 360 m2 for ordinary and 12.2 over 260 m2 for high.
The density is never reduced because a room is smaller than the design area (cl. 8.1.1 to 8.1.3). Storage hazards are driven by the head chosen and Annex C, with densities normally in the range of 25 to 50 lpm/m2 (cl. 8.1.4).
Hotels and homes divided into rooms use the room plus its communicating corridor as the design area (cl. 8.1.5, 8.8). Special heads change the area: extended coverage heads use the hazard area or the area of five heads, whichever is greater; ESFR heads use 12 heads, 4 on each of adjoining branch lines; large drop heads use a rectangle at least 1.2 times the square root of the operating area long (cl. 8.2).
Goods may be kept in ordinary hazard areas at the same density only in blocks of at most 50 m2 with 2.4 m clear around, and below 4.0, 3.0, 2.1 and 1.25 m for commodity categories I to IV (cl. 8.1.2, Table 6). Otherwise the whole occupancy is treated as high hazard.
| What | The rule | Source |
|---|---|---|
| Light hazard | 2.25 lpm/m2 over at most 84 m2 (cl. 8.1.1) | BIS, IS 15105:2021 |
| Ordinary hazard | 5 lpm/m2 over at most 360 m2 (cl. 8.1.2) | BIS, IS 15105:2021 |
| High hazard | 12.2 lpm/m2 over at most 260 m2 (cl. 8.1.3) | BIS, IS 15105:2021 |
| Storage hazard | Set by head type and Annex C; normally 25 to 50 lpm/m2 (cl. 8.1.4) | BIS, IS 15105:2021 |
Sprinkler spacing and coverage area as per IS 15105
For standard pendent and upright heads, one head covers at most 21 m2 in light hazard, 12 m2 in ordinary and 9 m2 in high, at no more than 4.5, 4.5 and 3.75 m apart (cl. 9.17).
| Clause | Light hazard | Ordinary hazard | High hazard | |
|---|---|---|---|---|
| Area per standard head, at most BIS, IS 15105:2021 | 9.17.1 | 21 m2 | 12 m2 | 9 m2 |
| Spacing between heads, at most BIS, IS 15105:2021 | 9.17.2 | 4.5 m | 4.5 m | 3.75 m |
| Spacing between heads, at least BIS, IS 15105:2021 | 9.17.3 | 1.8 m | 1.8 m | 1.8 m |
| Distance to a wall, at most BIS, IS 15105:2021 | 9.17.4 | Half the spacing; 1.5 m cap for combustible or open sides | Same | Same |
| Distance to a wall, at least BIS, IS 15105:2021 | 9.17.5 | 100 mm | 100 mm | 100 mm |
| Sidewall head: area, combustible ceiling BIS, IS 15105:2021 | 9.18.1 | 11 m2 | 7.5 m2 | Not listed |
| Sidewall head: area, non-combustible ceiling BIS, IS 15105:2021 | 9.18.1 | 18 m2 | 9 m2 | Not listed |
| Sidewall head: spacing along the wall, at most BIS, IS 15105:2021 | 9.18.2 | 4.3 m | 3 m | Not listed |
| Deflector below ceiling BIS, IS 15105:2021 | Table 8 | 75 to 450 mm non-combustible (300 preferred) | 75 to 300 mm combustible (150 preferred) | Exposed rafters: 75 to 150 mm |
These are values for standard heads only. Extended coverage, large drop, ESFR, extended sidewall and obstruction cases have their own clauses (cl. 9.19 to 9.24, Tables 9 to 16); read them in the standard. Area per head is the product of the two spacings or twice the wall distances (cl. 9.4).
Hazard classification as per IS 15105 and what it exempts
Clause 5 puts every occupancy in light, ordinary or high hazard, or storage; clause 6.2 lists the parts of a building where sprinklers are not provided.
If Offices, hotels, hospitals, schools, libraries, museums, places of worship, prisons or homes
Light hazard, excluding kitchens, stores and utilities, but only where no single compartment exceeds 126 m2 and compartments are separated by 30 minute walls and doors (cl. 5.2.2, 5.6.1). Otherwise design as ordinary hazard. BIS, IS 15105:2021
If Retail shops, car parks inside buildings, airport terminals, metro stations, laboratories, motor garages, electronics, garments, bakeries and similar
Ordinary hazard (cl. 5.3, 5.6.2). The list is not exhaustive; for an unlisted risk, write to the authority with full particulars before design (cl. 5.6). BIS, IS 15105:2021
If Processes with a high fire load that can spread fast
High hazard (cl. 5.4.1); some need water spray under IS 15325 instead (cl. 5.4.2). BIS, IS 15105:2021
If Warehouses and stores above the heights allowed in ordinary hazard
Storage hazard by commodity category, protected by Annex C densities (cl. 5.5, 8.1.4); ESFR heads reach storage up to 13.7 m (Table 1). BIS, IS 15105:2021
If Stairs, spaces under stairs, lift wells, or toilets under 5 m2
May be left without sprinklers if separated by walls and 120 minute fire doors (cl. 6.2.3). BIS, IS 15105:2021
If A dry electrical room in a 120 minute enclosure with no storage
Sprinklers not required if the five conditions of cl. 6.2.4 are all met; server rooms may use other extinguishing systems (cl. 6.2.3). BIS, IS 15105:2021
If Salt baths, metal melt pans, frying ranges or grain silos
No sprinklers, and no water pipes over them (cl. 6.2.2). BIS, IS 15105:2021
If Mixed hazards in one system
Size the water for each hazard and take the highest; a higher hazard confined to 40 m2 or less follows the dominant occupancy (cl. 13.2). BIS, IS 15105:2021
Sprinkler water tank capacity and pump duty in IS 15105
Table 30 sets exclusive sprinkler storage at 30, 60 or 120 minutes of pump running by hazard, with floors of 60 and 150 m3, and Table 29 gives the pump sizes; both apply only where SP 7 (Part 4) Table 7 is silent.
30 min
light hazard storage at pump capacity, or 60 m3 if greater (Table 30) BIS, IS 15105:2021
60 min
ordinary hazard storage at aggregate pump capacity, or 150 m3 if greater (Table 30) BIS, IS 15105:2021
120 min
high hazard and storage at aggregate pump capacity (Table 30) BIS, IS 15105:2021
2,850 lpm
ordinary hazard pump at 7.0 bar, the larger listed size (Table 29) BIS, IS 15105:2021
4,550 lpm
largest listed pump for high hazard and storage (Table 29) BIS, IS 15105:2021
20 percent
margin a pump must exceed the calculated flow and pressure (cl. 12.1(e)) BIS, IS 15105:2021
225 m3
reservoir size from which two interconnected compartments are needed (cl. 13.3(e)) BIS, IS 15105:2021
2 years
longest gap between reservoir cleanings (cl. 13.3(g)) BIS, IS 15105:2021
Sprinkler head selection under IS 15105: K-factor and temperature
Table 1 matches head K-factor to hazard and building height, and clause 7.7 sets the rating at least 30 degrees C above the hottest expected ceiling.
K 57 or 80, up to 9 m
Light hazard heads
K 57 or 80 up to 9 m of building height and K 115 above 9 m and within 15 m, pendent, upright or sidewall, quick or standard response (Table 1). BIS, IS 15105:2021
K 80 or 115, up to 9 m
Ordinary hazard heads
K 80 or 115 up to 9 m, K 115 for 9 to 15 m, pendent or upright (Table 1). BIS, IS 15105:2021
K 115 or 160, up to 9 m
High hazard heads
K 115 or 160 up to 9 m, K 160 and above for 9 to 15 m (Table 1). BIS, IS 15105:2021
ESFR, K 200 to 400
High storage heads
ESFR heads of K 200 to 400 up to 13.7 m, and in-rack heads of K 80 or more (Table 1). Orifices are 10, 15, 20 or 25 mm (cl. 7.4). BIS, IS 15105:2021
30 degrees C margin
Temperature rating
At least 30 C above the highest expected ceiling temperature (cl. 7.7.1); 141 C roof heads over high-piled storage (cl. 7.7.2); heads kept 750 to 2,000 mm from hot sources. BIS, IS 15105:2021
5 to 50 of each type
Spare heads
Light 5, ordinary 15, high 30 near a state capital (within 200 km), and 15, 25 or 50 elsewhere, kept at or below 38 C with a wrench (cl. 7.10, Table 5). BIS, IS 15105:2021
Sprinkler pipe size and pressure rules in IS 15105
Clause 10 says when pipe may be sized from tables and when a full hydraulic calculation is required, and caps pressure at 7 bar and water speed at 6 or 10 m/s.
Do
- Use a fully calculated system for high hazard, storage, any ESFR, large drop, extended coverage or intermediate heads, and any light or ordinary occupancy above 5,000 m2 of floor area (cl. 10.3.2). BIS, IS 15105:2021
- Keep arm and drop pipes feeding heads to 32 mm bore or less where the feeding pipe is over 65 mm (cl. 10.1(c)); use 32 mm minimum for rooms in offices and hotels (cl. 10.1(d)). BIS, IS 15105:2021
- Keep water velocity to 6 m/s through valves and flow devices and 10 m/s elsewhere (cl. 10.5). BIS, IS 15105:2021
- Keep the maximum installation pressure at or below 7 bar (cl. 10.3.3). BIS, IS 15105:2021
Don’t
- Pre-calculate a gridded or looped layout: tables are only for non-looped light and ordinary systems up to 5,000 m2 (cl. 10.3.1). BIS, IS 15105:2021
- Connect heads directly to distribution pipes, except light hazard on pipe up to 50 mm (cl. 10.1(b)). BIS, IS 15105:2021
- Assume pre-calculated pressure is the same everywhere: Table 22 gives 225 lpm at 2.2 bar for light and 1,800 lpm at 2.02 bar for ordinary, both plus static losses, at the installation valve. BIS, IS 15105:2021
Sprinkler system maintenance as per IS 15105
Clause 15.6 and Table 31 run from a daily pump run to a two-yearly painting; heads are inspected and discharge-tested at least every 6 months and the system is flushed at least yearly.
Daily (cl. 15.6.3, 15.6.4)
Run every fire pump for at least 5 minutes and log priming tank level, pressures and speed; read the gauges above and below the installation valve at the start of the first shift. BIS, IS 15105:2021
Weekly (cl. 15.6.1, 15.6.2)
Visual check of the system, gauge readings recorded, reservoir level recorded and kept full, pump glands and starter contacts checked, and the alarm gong timed after the drain valve is opened. BIS, IS 15105:2021
Every 3 months (cl. 15.6.4)
The alarm gong assembly is checked thoroughly; Table 31 adds quarterly sprinkler cleaning, flow test and a performance check. BIS, IS 15105:2021
Every 6 months (cl. 15.6.4)
Every head is inspected for position, loading and corrosion, a discharge test is made, and pump motor insulation resistance is measured. BIS, IS 15105:2021
Yearly (cl. 15.6.4)
Pipework is examined, installation valves are serviced and tested by qualified people, and the system is flushed. BIS, IS 15105:2021
Twice a year (cl. 15.6.4)
Manual checking devices are operated at least twice annually. BIS, IS 15105:2021
Every 2 years (cl. 13.3, 15.6.4)
Reservoir cleaning at least this often and painting of all sprinkler equipment. BIS, IS 15105:2021
Always (cl. 15.2 to 15.5)
A shutdown needs planning, notice to the authority and extra fire precautions; reopen every closed valve and replace operated heads after a fire. BIS, IS 15105:2021
IS 15105:2021 acceptance tests before a system goes live
Clause 14 puts a 120 minute pressure test at 150 percent of working pressure, flushing, a flow test and a diesel pump start sequence between installation and use.
Documents
The installer checks working drawings against what was built and lists deviations for the authority's approval (cl. 14.1). BIS, IS 15105:2021
Pressure test
Pipework from the pump house to the installation valve and the head pipework must hold 150 percent of maximum working pressure for 120 minutes (cl. 14.2(a)). Pre-action systems also take a 3 bar air leak test for 24 hours (cl. 14.2(c)). BIS, IS 15105:2021
Flushing and balance
Flush all piping at the maximum flow available; where a building and its connected buildings exceed 500 heads, check hydraulic balance at the best and worst locations (cl. 14.4). BIS, IS 15105:2021
Flow test
Prove by a full-flow test that the water supply matches the accepted drawings, by operating a bulb or the pump-room test line, and record the results (cl. 14.5). BIS, IS 15105:2021
Pump start
Diesel pump: isolate fuel and run 6 cycles of at least 15 s cranking and at most 15 s rest; the fail-to-start alarm sounds; restore fuel and start manually (cl. 14.7). BIS, IS 15105:2021
Alarms
The gong must sound within 45 to 60 seconds of flow (cl. 11.10(b)) and be 85 dB above background noise (cl. 14.8(b)); signals must reach the panel (cl. 14.9). BIS, IS 15105:2021
IS 15105 vs NFPA 13: how the two sprinkler codes compare
Both codes classify hazard, cap area per head and the spacing; the IS 15105 limits of 21, 12 and 9 m2 sit close to the US figures of about 21, 12 and 9 m2 reported for NFPA 13, but Flamekite has not read NFPA 13.
- Hazard classes
- IS 15105 has four (light, ordinary, high, storage; cl. 5.1). NFPA 13 uses light, ordinary and extra hazard with sub-groups; the exact mapping to IS 15105's high hazard is not confirmed. NFPA 13 summarynews report
- Area per head
- IS 15105: 21 m2 light, 12 m2 ordinary, 9 m2 high (cl. 9.17.1). A secondary summary of NFPA 13 gives 225, 130 and 100 ft2, about 21, 12 and 9 m2, with 15 ft (about 4.6 m) maximum spacing for light and ordinary. NFPA 13 summarynews report
- Design density
- IS 15105 fixes 2.25, 5 and 12.2 lpm/m2 (cl. 8.1). NFPA 13 sets density and area from curves; its values were not verified here, so no conversion is offered. BIS, IS 15105:2021
- Which one applies in India
- IS 15105 is the Indian standard named in Indian fire rules; NFPA 13 appears in insurer and multinational specifications. A tender must say which one governs. BIS, IS 15105:2021
Myths about IS 15105 and sprinkler design
Five common claims about IS 15105 that the 2021 text does not support.
You may have read
IS 15105:2002 is still the current sprinkler code.
Myth
What the sources say
BIS withdrew the 2002 edition on 14 March 2022; IS 15105:2021 is current, though some state lists still show the old edition. BIS standards database
You may have read
Sprinkler tanks must always follow IS 15105 Table 30.
Myth
What the sources say
For building groups A to F and some of G and H, Table 7 of SP 7 (Part 4) governs water and pumps; Table 30 covers only the rest (cl. 1.6, 13.1(a)). BIS, IS 15105:2021
You may have read
Every head in the building opens when one operates.
Myth
What the sources say
Heads open one by one as each is heated; the design area is the largest area assumed to operate, such as 360 m2 for ordinary hazard (foreword, cl. 8.1.2). BIS, IS 15105:2021
You may have read
Sprinklers make hydrants, extinguishers and alarms unnecessary.
Myth
What the sources say
The foreword says sprinklers do not remove the need for other means: egress, alarms, hose reels, hydrants and extinguishers all need consideration. BIS, IS 15105:2021
You may have read
One partial sprinkler zone is fine anywhere.
Myth
What the sources say
The whole block must be sprinklered unless the part is an allowed exception or is cut off by fire walls and doors (cl. 9.1(a), 6.2). BIS, IS 15105:2021
IS 15105:2021 traps: where the code differs from itself
Three places where the 2021 text gives two values, so the stricter reading matters until the fire office says otherwise.
If Flushing is at least yearly in cl. 15.6.4(g) but Table 31 lists main piping every 2 years and the sprinkler pipe network every 6 months.
Follow the yearly clause as a floor, and ask your AMC contractor which table row the contract uses. BIS, IS 15105:2021
If Discharge and flow tests are 6-monthly in cl. 15.6.4(c) but Table 31 lists the sprinkler flow test and cleaning as quarterly.
Plan for quarterly checks on a high-value site and treat 6 months as the minimum. BIS, IS 15105:2021
If Ordinary hazard design flow is 1,800 lpm at 2.02 bar in Table 22, but cl. 10.4.6 asks for the pressure loss at 1,000 lpm.
Have the designer state which rate each calculation sheet uses before the layout is submitted. BIS, IS 15105:2021
IS 15105:2021 applied: an office floor, a store, a tank and a pump
Flamekite’s working from the official rules; no government publishes this figure.
Four readings of the clauses by Flamekite's own arithmetic. They are not design drawings, and the ones on water assume Table 7 of SP 7 (Part 4) does not already cover the building.
Case 1
Light hazard office
1,000 m2 floor, standard pendent heads, no compartment over 126 m2
What applies At 21 m2 a head, at least 48 heads (1,000 / 21, rounded up), and 4.5 m spacing gives 20.25 m2, so about 49 to 60 in practice. Design flow 2.25 x 84 = 189 lpm (cl. 8.1.1, 9.17). Offices follow /fire-noc/offices for the NOC side. BIS, IS 15105:2021
Case 2
Ordinary hazard retail or car park
2,400 m2 at 12 m2 a head
What applies At least 200 heads. Design flow 5 x 360 = 1,800 lpm (cl. 8.1.2), which matches the 1,800 lpm in Table 22 for a pre-calculated system. See /fire-noc/malls for the NOC. BIS, IS 15105:2021
Case 3
Ordinary hazard tank
Pump of 2,850 lpm, hazard not in SP 7 Table 7
What applies 60 minutes gives 171 m3, which exceeds the 150 m3 floor, so 171 m3 (Table 30); a 2,280 lpm pump gives 137 m3, so the 150 m3 floor applies. Add 30 m3 if no hydrant system backs it (cl. 13.1(f)). BIS, IS 15105:2021
Case 4
High hazard store with a pump
Storage hazard with a 4,550 lpm pump
What applies 120 minutes gives 546 m3 of storage (Table 30), well above 225 m3, so two interconnected compartments with a common sump (cl. 13.3(e)). Storage density and head type are from Annex C. See /fire-noc/warehouses. BIS, IS 15105:2021
IS 15105:2021 details this page could not confirm
Gaps are listed rather than guessed.
- NFPA 13 values: the NFPA text was not read, only a secondary summary, so no density or area comparison is given. NFPA 13 summarynews report
- Amendments to IS 15105:2021: none appear in the text read, but the BIS record of amendments was not checked. BIS, IS 15105:2021
- Which sprinkler thresholds apply to which building: they sit in SP 7 (Part 4), which this page did not read for the table; see /national-building-code-2026. BIS, SP 7:2026
- Which state fire rules name the 2021 edition: only Maharashtra's Note 21(a) is known, and others may cite the 2002 edition. BIS standards database
- Obstruction tables (9 to 16), pipe sizing tables (17 to 28), annexes and figures are not reproduced; read them in the standard, free after registration with BIS. BIS, IS 15105:2021
Questions about IS 15105:2021
What is IS 15105?
- IS 15105 is the Indian Standard code of practice for the design, installation and maintenance of fixed automatic sprinkler fire extinguishing systems. The current edition is IS 15105:2021, the first revision, from the Fire Fighting Sectional Committee, CED 22.
What is the latest version of IS 15105?
- IS 15105:2021, published in July 2021. It replaced IS 15105:2002, which BIS withdrew on 14 March 2022.
What is the sprinkler spacing as per IS 15105?
- For standard pendent and upright heads the maximum spacing is 4.5 m for light and ordinary hazard and 3.75 m for high hazard, with a minimum of 1.8 m (cl. 9.17.2, 9.17.3).
What is the sprinkler head coverage area as per IS 15105?
- At most 21 m2 for light hazard, 12 m2 for ordinary and 9 m2 for high hazard for standard pendent and upright heads (cl. 9.17.1). Sidewall heads cover 7.5 to 18 m2 depending on hazard and ceiling (cl. 9.18.1).
What are the hazard classes in IS 15105?
- Light, ordinary (moderate), high and storage hazard (cl. 5.1). Light hazard compartments are limited to 126 m2 and offices, hotels and homes are listed as light hazard (cl. 5.2.2, 5.6.1).
What is the design density in IS 15105?
- 2.25 lpm/m2 over 84 m2 for light hazard, 5 lpm/m2 over 360 m2 for ordinary and 12.2 lpm/m2 over 260 m2 for high hazard (cl. 8.1).
What is the sprinkler water tank capacity as per IS 15105?
- Table 30 gives 30 minutes of pump capacity or 60 m3 for light hazard, 60 minutes or 150 m3 for ordinary and 120 minutes for high hazard and storage, for occupancies not covered by Table 7 of SP 7 (Part 4).
What pipe size does IS 15105 allow?
- The code sets a method, not one size: tables for small light and ordinary systems up to 5,000 m2 and hydraulic calculation for the rest, with arm pipes of 32 mm or less in ordinary and high hazard (cl. 10.1, 10.3).
How often is a sprinkler system maintained as per IS 15105?
- Pumps are run daily for 5 minutes, gauges logged weekly, every head inspected and discharge-tested at least every 6 months, and the system flushed at least yearly (cl. 15.6).
Is IS 15105 mandatory?
- Not by itself. No Quality Control Order covers the code, and the sprinkler head order was only a draft on 24 October 2026. It binds when a rule, NOC condition or contract names it.
Keep reading
- Sprinkler system MCQ44 practice questions on IS 15105, every answer cited to its clause.
- IS codes for fire safetyEvery core fire standard with its current edition and QCO status.
- IS 2190: fire extinguishersRefill, hydro test, count and life of portable extinguishers.
- IS 2189: fire detection and alarmThe alarm code that sits beside the sprinkler system.
- National Building Construction Standards 2026SP 7:2026, whose Part 4 table sets water and pumps for most buildings.
- Fire AMCHow these test intervals become a maintenance contract.
- Fire auditHow an auditor checks sprinklers against the code.
- Fire NOC for warehousesStorage hazard and sprinkler design for stores.
Keep exploring
More in Fire Safety IS Codes
Sources
Each source was opened and read on the date shown. How Flamekite checks its sources
- Bureau of Indian Standards: IS 15105:2021, Design, Installation and Maintenance of Fixed Automatic Sprinkler Fire Extinguishing Systems, Code of Practice (first revision), July 2021; free download after registration; clause and table numbers cited on the page (opens in a new tab)
- Bureau of Indian Standards, Know Your Standards database: Status records read 25 October 2026 for IS 2189, IS 2190, IS 15683, IS 16018, IS 3844, IS 13039, IS 15105, IS 15301, IS 9668, IS 12349, IS 3614, IS 2175 and IS 11360 (current or withdrawn, with dates) (opens in a new tab)
- Bureau of Indian Standards, Know Your Standards database: Status, publication and withdrawal dates of the fire standards named on /is-codes (IS 2190, 15683, 16018, 2189, 15105, 9972, 3844, 13039, 9668, 15301, 15908, 636, 884, 903, 5290, 9457, 3614, 11360, 2175 and others), read 24 October 2026 (opens in a new tab)
- Bureau of Indian Standards: Products under compulsory certification, Scheme-I list (orders up to S.O. 5480(E) of 6 October 2026), read 24 October 2026 (opens in a new tab)
- Bureau of Indian Standards (copy hosted by Goa Directorate of Fire and Emergency Services): SP 7:2026 National Building Construction Standards 2026, Part F: Fire and Life Safety (opens in a new tab)
- Callout (code summary site): NFPA 13 2022 section 8.5.1, sprinkler spacing and coverage: a secondary summary, not the NFPA text (opens in a new tab)