delaying heat = fire rated ?

[ludwig80]

Article 11.1.2 (1) (NFPA-13, ed.2007) can be read as : “ Where areas are not physically separated by a barrier or partition capable of delaying heat from a fire in one area from fusing sprinklers in the adjacent area, the required sprinkler protection for the more demanding design basis shall extend 15 ft (4.6 m) beyond its perimeter. “

Does that barrier need to be fire rated? At first sight, I would say no because NFPA does not mention such thing. But, if the partition is not fire rated, it would mean that it cannot prevent fire entering other room for a certain amount of time.

What do you think? Would a typical gypsum wall arrangement be enough to meet article 11.1.2?

Thank you for your replies.

 

[cdafd]

"capable of delaying heat"

It appears that the section just wants the heat slowed down.

the wording for high piled stock is "permanent partition"


and how often does this condition actualy occur???

Maybe not worded to well???

 

[LCREP]

The purpose of the barrier or my commonly called a draft curtain is to prevent the heat from the fire fusing sprinklers not in the same fire area. I have scene 22 gauge sheet metal, treated fabric, etc. A gypsum wall arrangement would be fine, over kill, but OK. The draft curtain will only need to extend 2 feet below the roof deck. See link below for the fabric curtain. Why not extend the sprinkler design area 2 more branch lines i.e. the 15' and be done with it. Most times I see a draft curtain when an ESFR and non-ESFR systems are used in the same area.

http://www.smokeandfireprevention.com/curtain.htm

****************************************
Fire Sprinklers Save Firefighters’ Lives Too!