Hose stream allowance and Fire hose cabinets 1

[orator]

I have a question regarding Hose stream allowance. NFPA13- Table 11.2.3.1.2 provides information about Hose Stream allowance. Please let me know what exactly is hose stream allowance. If I provide 100 gpm hose stream will it be discharged at fire hose cabinet. To my Understanding I always considered Fire hose cabinets to be a part of Standpipe system. Please make me understand how hose stream allowance is different from Standpipe System.

 

[TravisMack]

From NFPA 13, 2013:

A.11.4.2

The hose stream demand required by this standard is intended to provide the fire department with the extra flow they need to conduct mop-up operations and final extinguishment of a fire at a sprinklered property. This is not the fire department manual fire flow, which is determined by other codes or standards. However, it is not the intent of this standard to require that the sprinkler demand be added to the manual fire flow demand required by other codes and standards.

That should explain pretty well what the hose stream allowance is.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

 

[Sdpaddler50]

Sprinkler demand plus the hose stream allowance less than the water supply...if yes, you are good.

 

[orator]

Travis, Thanks for the answer but where these fire department people will get the extra flow from? I am not providing any hose in the building because what I understand is any hose connection or fire hose cabinet is a part of standpipe system which is not required in my building. I only have sprinklers in my building. Hose stream allowance is now clear to me but from where it is being used is still not clear. Please help

 

[skdesigner]

NFPA 13-2010 Table 11.2.3.1.2 has three options for inside hose: 0, 50 or 100. The next column to the right is called total combined inside and outside hose. For light hazard, this is 100 gpm. From this, we can deduce that there are times when no inside hose is needed (meaning the 100 gpm would need to be classified as outside hose).

11.1.6.4 states "Water allowance for outside hose shall be added to the sprinkler requirement at the connection to the city main or a private fire hydrant, whichever is closer to the system riser."

When the fire dept. conducts mop up operations, they will connect to the nearest fire hydrant to do it. This where the hose allowance comes in to play.

 

[Adnan86]

Thanks Skdesigner. Now its clear.