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Hydrant Flows Highrise buildings

Question asked by pwalker on Jan 31, 2019
Latest reply on Feb 4, 2019 by genglishucs

With respect to hydrant Fire Flows for High-rise buildings that are sprinklered to NFPA 13.

 

I have researched a Multiple of standards NFPA 13,14,24,1142,and 101 in an attempt to locate recommended hydrant flows for high-rise buildings . Currently I’m attempting to gain access to SFPE Code Official’s Guide to Performance-Based Design Review that is referenced in a number of the standards.   

 

The following are excerpts from NFPA standards.  

 

NFPA 1143

 

3.3.16 Municipal-Type Water System. A system having water pipes servicing fire hydrants and designed to furnish, over and above domestic consumption, a minimum of 250 gpm (950 L/min) at 20 psi (138 kPa) residual pressure for a 2-hour duration. [1141, 2012]

 

Which in this case I  don’t believe 1142 would not be appropriate standard.

 

NFPA 14

 

Nfpa 14 has a higher level of water flow requirements:

 

Nfpa 14 10.1.3.2 For a combined system in a building equipped with

partial automatic sprinkler protection, the flow rate required

by 7.10.1 shall be increased by an amount equal to the hydraulically

calculated sprinkler demand or 150 gpm (568 L/min) for

light hazard occupancies, or by 500 gpm (1893 L/min) for

ordinary hazard occupancies, whichever is less

 

7.10.3 Maximum Flow Rates for Individual Connections.

7.10.3.1 The maximum flow required from a 212 in. (65 mm)

hose connection shall be 250 gpm (946 L/min).

7.10.3.2 The maximum flow required from a 112 in. (40 mm)

hose connection shall be 100 gpm (379 L/min).

7.10.4 Sprinkler System Hose Demand. Sprinkler system hose

demand in fully sprinklered buildings shall not be required to

be added to standpipe calculations

 

The British Columbia  building code has a minimum residual pressure of 690 kpa or 100 PSI  in standpipes but no GPM .

 

 

Our Municipal standard for fire flows is as follows:

 

FIRE FLOW DEMANDS

Fire flows shall be based on the publication "Water Supply for Public Fire Protection - A

Guide to Recommended Practice 1999" published by Fire Underwriters Survey except

that the minimum acceptable fire flows shall be:

 

Zone Required Fire Flow

Residential except Compact Lot Residential 60 l/s 900 usgpm

Suburban Residential 60 l/s 900 usgpm

Multiple Family, Compact Lot Residential, Comprehensive 90 l/s 1380 usgpm

Commercial & Institutional 150 l/s 2340 usgpm

Industrial 225 l/s 3540 usgpm

 

WATER PRESSURES

Maximum allowable pressure 1035 kPa 150 psi

Minimum pressure at Peak Hour Demand 300 kPa 43 psi

Minimum pressure anywhere in system during design 150 kPa 21 psi

Fire Flow and Peak Day Demand

 

 

Could you provide some guidance for hydrant flows for high rise occupancies from an NFPA perspective.

 

 

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