Clean agent question

[cdafd]

Clean agent system

1. air sampling system with sampling tubes at the ceiling and about half way down the room, same spacing for both.

2. smoke detectors at about the half way point down from the ceiling, mounted on large opening metal grid rail.

sequence is

a. two smokes set of system

or

b. one smoke, and air sampling alert, sets off system

anyone seen the smokes mounted more then a foot down and accepted it???

 

[rbulsara]

It depends on the ceiling height and construction. There would be a need for smoke detectors mounted at different heights to over come smoke stratification, for high ceiling areas.

But there will always be detectors at or near the highest point, that is on the ceiling. I would assume you are familiar with NFPA 72.

There are many other factors that affect smoke det spacing and locations.


Rafiq Bulsara

http://www.srengineersct.com

 

[pipesnpumps]

What catches my attention is the smokes are halfway down, and yet at least one is required to detect for either scenario (a or b)..

What if the plume does not hit a detector on the way up, and the smoke does not stratify due to bouyancy? It would require all the space above the open grid to fill with smoke before activating.

Maybe that is the intent. I can't answer the question specifically, but it is an interesting topic.