What is Req'd Pressure and Flow for Hydrants?

8/28/2020

What is the residual pressure and flow require for both public and private fire hydrants?

Submitted anonymously and posted for discussion. Discuss This | Submit Your Question | Subscribe

7 Comments

franck

8/28/2020 10:38:35 am

For public, I don’t know minimum requirements in the US.
In Europe, it depends on occupancy to protect and is normally 250 gpm per hydrant @ 15 psi, with a minimum number of operating hydrants (from 1 to 6)

For private, based on occupancy.
You will find guidance in NFPA and is usually 250 gpm for low hazards and 500 gpm for high hazards and storage. But may also vary, such as with the use of ESFR.
Note that some occupancies may require up to 750 gpm.
And some insurance companies / AHJ may have larger requirements

Naseer Pasha link

8/28/2020 10:50:46 am

Required Private Fire Hydrants shall be capable of discharging 1000gpm @ 20psi minimum as per IBC & NFPA 1 & 101.

Sheikh

8/28/2020 11:50:39 am

Can you please prove the reference of IBC, NFPA 1 and 101?

Although NFPA 24 provides some information of placing.

sean

8/28/2020 02:15:34 pm

I do not use NFPA 1 or 101 as often I will concentrate on the ICC model codes.

It actually comes from the IFC and it does not state those amount unless you use the appendix.

The code section is 507.3 (IFC 2018) which calls for fire flow to be per an approved method. It does not specify which method to use

8/28/2020 12:26:17 pm

Residual pressure and flow requirement are dependent for which client, Country, AHJ or occupancy working for?

As inference from NFPA 13, Hydrant flow/Hose stream flow varies from 250 gpm to 750 gpm but there is no there is no single criteria.

Similarly for residual pressure, it's depend and also varies from 20 psi (1.4 bar) to 100 psi being the max. More than 100 psi hose can not be handled by safety by personnel as per OSHA guidelines...Where i am working, here is 00 psi (7 bar) is minimum requirement and I've also seen some other country it's 65 psi as well. May refer NFPA 24 C.4.1, NFPA 14 7.2.3.1 & 7.8, NFPA 13. One of the argument is for not maintaining high residual pressure is unnecessary keeping the system pressurized/stress all the time when no fire/emergency and wastage of powers, in any case, whenever it's required, pumps kicks on to meet the pressure needed. So maintaining is lower pressure is also acceptable.

sean

8/28/2020 02:16:52 pm

NFPA 13 does not influence hydrant design the fire code (IFC, NFPA 1) and NFPA 24 do.

Franck

8/31/2020 03:51:14 am

My understanding is that NFPA 13 requirements are for minimum flow demand (manual firefighting) considering that the entire facility is adequately protected by sprinklers.
NFPA 1 requirements are for minimum waterflow to be available for buildings. This may not take into consideration if the building is adequately protected or not, and this flow is to feed the hydrants + hoses + possible sprinkler systems.
Which means that if you have sprinkler systems inside your building (with a corresponding flow and pressure) fed by the same water supply, you would have less water for hydrants + hoses.

But maybe it is a misunderstanding from my side.

If somebody could clarify this for me that would be great.

What is Req'd Pressure and Flow for Hydrants?

Leave a Reply.

ALL-ACCESS

SUBSCRIBE

COMMUNITY

YOUR POST

PE EXAM

FILTERS

ARCHIVES

PE PREP SERIES