| Primary value | 2280 L/min ((38 L/s)) |
| Applies to | High-rise buildings (> 15 m height) · Buildings with fire hydrant + sprinkler systems |
| Exceptions | Smaller buildings (15-24 m height) → 1620 L/min (27 L/s) min |
| Standby diesel pump → Same capacity as electric pump | |
| Jockey pump (pressure maintenance) → 180 L/min | |
| High-hazard occupancies (industrial, storage) → 2850 L/min (47.5 L/s) | |
| Buildings > 45 m height → Requires an additional terrace tank and fire pump (typically 900 L/min). | |
| Combined systems with higher-demand sprinklers (e.g., Ordinary Hazard Group 2/3) → Capacity as per hydraulic calculations per IS 15105, which may exceed the hydrant demand. | |
| Measured as | Discharge capacity at the rated pressure (typically 7.0 kg/cm² at the hydraulically most-remote outlet). |
| Source | NBC 2016 — NBC 2016, Part 4, Annex E, Table E-1 and Clause E-4. The cited IS 12469 is incorrect; relevant codes for system design and installation are IS 15105 and IS 15301. ✓ Verified |
The specified capacity ensures sufficient water flow and pressure to operate a pre-determined number of fire hydrants and/or a calculated area of sprinklers simultaneously, as per code. An undersized pump can lead to a catastrophic failure of the fire suppression system during a major fire event, as pressure drops when multiple outlets are used.
Standard practice for high-rise buildings involves one primary electric pump and an identical 100% standby diesel pump to ensure operation during power failure. A smaller jockey pump (typically 180 L/min) maintains system pressure against minor leaks, preventing the main pumps from frequent cycling.