Note: only “assembly occupancy” has a specific requirement in NFPA 101 – check 12.4.5.12
Within the context of a building, a standpipe serves the same purpose as a fire hydrant.
A Dry Riser is a system of valves and pipework which enables the Fire Service to pump water into an inlet valve outside the building towards outlet valves inside the building. They will take hoses into the building and connect these to the required outlet valve. The pipework remains empty until the Fire Service fill the system with water.
A Wet Riser is a similar system of valves and pipework which are kept permanently charged with water.
Dry risers will be found in buildings over 18 metres above ground level, or in low level buildings where there are excessive distances from entrances (60m).
Wet risers will be found in buildings over 60 metres above ground level.
The Fire Hose Station should be clearly visible beside the exit way or stairway (maximum allowed 6 meters from exit way or exit staircase). Additional fire hose stations along the exit access corridor, horizontal exit or in the car park floors shall be installed such that all portions of each floor are within 30 m from the fire hose station while measured along the natural path of travel from the hose station.
Fire Pump shall be located at the lowest level of the building, pumping water upwards. Fire pumps at levels higher than the lowest level of the building with water supply feeding downwards is not allowed.
Dry riser stand pipe system shall be terminated to a 2-way breeching inlet connection having 100 mm dia flanged outlet with 2 nos of 65 mm instantaneous male coupling inlets, located at Fire Access level for Civil Defense.
Multiple wet risers’ zoning system shall be established in high rise buildings where pressure reducing valve station is utilized with single fire pump set instead of multiple pumping station, to restrict pressure limit with in 12 bar at any landing valve outlet.