Fire hydrant installation consists of a system of pipework connected directly to the water supply mains to provide water to each and every hydrant outlet and is intended to provide water for the firefighters to fight a fire. The water from hydrant is connected into the fire engine from which it is then pumped and then delivered through hoses into the fire. Where the water supply is not reliable or inadequate, hydrant pumps will be designed to pressurize the fire mains.
Codes and Standards
Fire hydrant shall be designed, tested, selected, installed and maintained in accordance to:
- MS1489 : Part 2 – Fire Extinguishing Installations and Equipment : Wet and Dry Firefighting Mains.
- MS 1395 : Specification for Pillar Hydrant.
- Any relevant International or Regional Standards
Hydrant Outlets
Where fire hydrants are installed, they should be positioned not more than 90 metres from an entry to the building and should be 90 metres or less apart. Underground fire hydrants should be designed in accordance with BS 750 and BS EN 14339. Siting of underground fire hydrants in roadways should be avoided but where necessary the frame and cover should be in accordance with BS 750 and capable of bearing the heaviest vehicle anticipated to use the roadway.
Fire hydrants should comply with M.S.1395 or relevant Standards and located at not more than 30 metres away from the breeching inlet of a building. For highrise buildings, fire hydrant should be located more than 6 metres from the building to prevent firefighter injuries from falling debris. Generally, hydrants are spaced at 90 metres or less apart along access roads of minimum 6 metres in width and capable of withstanding a load of 26 tons from fire brigade vehicles. Hydrant outlets are typically of the twin or tri-outlet pillar type. For private properties, each hydrant shall come with a steel hydrant cabinet equipped with 2 lengths of 30 metres of 65mm diameter canvas hose complete with instantaneous couplings and nozzles. Public area fire hydrants located along road sides need not to be provided with hose cabinets as fire hoses are available on fire trucks at site.
Fire hydrants with twin outlets should be capable of delivering 1,000 litres/min of water at a minimum water pressure of 4 bars but not exceeding 7 bars for instantaneous coupling with hoses (private properties), while pressure for threaded type of hydrant outlets are permitted to exceed 7 bars. The 1,000 litres/min total output per hydrant is based on each 65mm diameter double outlet, discharging 500 litres/min simultaneously. Pressure regulating type of outlet valves should be used where the pressure from the fire mains exceed 7 bars. The hydrant mains are usually laid underground although they can also be installed above ground except where it crosses a road. The piping is usually of cement lined steel pipe. However, piping of approved PPR or HDPE material may also be used where corrosion is a major concern.
