Talk with a fire inspector yesterday made me rethink our machine room setups

Was doing a routine mod in a 12 story office building downtown. Fire inspector walks in while I'm swapping out a controller. He points at the gaps around our drive cables and asks about fire stopping. Told him we seal them standard. He says 'yeah but I bet you don't check the floor penetrations above the machine room.' Went up two floors and sure enough, there was a 3 inch hole where some other trade ran fiber. That would have sucked smoke right into the cab shaft in a fire. Never once thought to look above the room itself. Anyone else had inspectors catch stuff like that?

3 comments

3 Comments

bell.felix7d ago

Yeah, that line about checking above the machine room really got me. I used to think the same way, just focus on what I could see from inside the room. But now I'm gonna start looking at the floors right above and maybe even below, like you said. It's one of those things that seems so obvious after someone points it out. Never crossed my mind that smoke could come from a floor above and just drop down through a gap.

jennifer2047d agoMost Upvoted

Smoke is actually more likely to rise than drop straight down through gaps like that. The heat from a fire usually pushes it up into higher floors, not below. You might still want to check above the machine room, but I wouldn't expect smoke to fall down from the floor above without some weird air pressure stuff going on.

taylorc407d ago

Honestly, a buddy of mine in Tampa had something similar happen. He was doing a PM on a newer building and the inspector noticed the fire caulking around the sprinkler riser looked fresh. Inspector asked when that was last done, and my buddy said "last month." Turns out the caulking was fresh because some other crew had cut into it to run new alarm wire and never bothered to seal it back up. The inspector made him open up the whole drop ceiling to check for more of that stuff. Found three other spots where they'd done the same thing.