How do you calculate fire water requirements?

The basic formula in the schedule is: NFFi= (Ci)(Oi)(X +P)i Where NFFi = needed fire flow (NFF) in gal per min (L/min) Ci = a construction factor that depends on the construction of the structure under consideration Oi = an occupancy factor that depends on the combustibility of the occupancy (X = P)i = an exposure …

How do you calculate GPM needed?

The formula to find GPM is 60 divided by the seconds it takes to fill a one gallon container (60 / seconds = GPM). Example: The one gallon container fills in 5 seconds. 60 / 5 = 12 GPM. (60 divided by 5 equals 12 gallons per minute.)

What is fire flow rate?

Fire flow is defined as the flow rate of a water supply, measured at 20 psi (137.9 kPa) residual pressure, that is available for the responding fire department for manual firefighting, typically this is water that is available at the surrounding fire hydrants, but it can be supplied with another approved source such as …

What is fire flow requirement?

Minimum fire flow shall be 1000 gallons per minute (GPM) for one-and-two family dwellings less than 3,600 Ft². Dwellings greater than 3,600 Ft² shall meet the fire flow requirements of the 2016 California Fire Code, Appendix B, and Table B105. 1.

What is the minimum flow in gallons per minute required for firefighting demand?

1500 gallons per minute
B105. 4 to determine the total required fire-flow, but in no case shall the resulting fire-flow be less than 1500 gallons per minute (5678 L/min) at 20 pounds per square inch (138 kPa) residual.

How do you calculate fire flow?

National Fire Academy Formula The NFA fire flow formula is: Required fire flow (gpm) = (length x width) ÷ 3. Using the same example, an IC arrives at a burning mercantile occupancy that measures 50 feet by 75 feet and is one story tall. The IC quickly determines that the area of the structure is 3,750 square feet.

How many GPM can a fire hydrant flow?

CLASS Hydrants that on individual test usually have a flow capacity of:
CLASS AA 1,500 gpm or greater
CLASS A 1,000 gpm or greater
CLASS B 500 to 1,000 gpm
CLASS C <500 gpm

How do you do a fire flow test?

Conduct the test

  1. Record static pressure reading from gauge cap.
  2. Slowly open hydrant using the gate valve to purge air from the hydrant. When hydrant is full of water, open gate valve to desired flow-rate (usually full open).
  3. When the flow-rate stabilizes,
  4. Record nozzle pressure from the remote reader.

How many GPM can a 3 inch pipe hold?

Water Flow Capacity in Steel Pipes (sch 40)

Pipe Size Maximum Flow (gal/min) Head Loss (ft/100 ft)
2″ 45 3.9
2-1/2″ 75 4.1
3″ 130 3.9
4″ 260 4.0