Fire Hydrant Pressure

Pl. describe why the hydrant pressure is 7 kg/cm2
-Subodh

Normally, at the battery limit of the plant (which includes, structures, columns, & Vessels which are nearly 50 m high or so as per the design need), the pressure of the Fire hydrant system will be 5 Kg/cm2. In order to maintain that considering the pressure losses and line losses, it is normal to maintain the Fire hydrant pressure at 7 Kg/cm2. Any thing more than that is energy waste. Anything less than that will create problems during fire crisis. Hope this clarifies. If you need detailed clarification, pls consult a piping and HSE expert in this.

it is as per the standards and depend up on the type of occupancy it may vary from 7 kg/cm2 to 12 kg/cm2 depending upon the type of occupancy

With reference to the above I hv few questions mentioned below
. Pressure standard decided by NFPA body or any other
. 7kg/cm² to 12/cm² means how much litter water will come per min.

Hydrant mains should be tested with the pump delivering at its maximum pressure with all the hydrants outlet closed and thereafter, with at least three adjacent hydrants opened to see that the hydrant yield the minimum output of 1125 litres per minute at a minimum pressure of 5.25 kgf/cm2
as per IS13039:1991 (External hydrant systems provision and maintenance code of practice)
Regards,
PARAG BANE
Safety & Environment (Birla Carbon)

Hi Parag sir,
Thank you very much for ur quick response now out,of curosity how the calculation done, if 7kg/cm2 then how much litter would come out per min, way to calculate it plz

Dear Ashok,
for calculation :- it depend on no. of hydrant points, pump capacity, head, length of line etc.

Respected sir,
I just want to know the lpm if it's between 7 to 12kg/cm2 n the basic way to calculate it, sir plz help me to get this answer it's really required for me to know please.
Thanks n regards
Ashok K