Fire Curtain Question

Jason BAnks

Member
Hi All,
I am looking for a regulation. I have always heard that when running cables for audio, video, lighting for a production that you should not run those lines across a Fire Curtain line because of electrical safety in the case of the fire curtain dropping and sheering the cables. Is this regulation? If so can anyone cite source? I haven't been able to find it.
 
I've never heard of a fire curtain being able to actually cut something crossing it, the issue I've always heard raised is whether or not it will allow the curtain to properly seal to the ground and complete the barrier. So a set piece couldn't cross because it would leave an opening. Our AHJ allows *some* runs, an xlr here and there, roughly 1/4" because of the way the fire curtains are designed they bury themselves on the deck a little, so a small diameter would still allow it to properly seal to the ground around it. We still don't do it but they'd find it acceptable in our venue at least. I *know* I've read the code that pertains to this but I definitely can't cite it.
 
NFPA 80 chapter 20 regulates fire curtains. They must have what is known as a bumper (yield pad) that forms a seal to the deck. This seal can not be interrupted by any objects, like cables.
 
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NFPA 80 chapter 20 regulates fire curtains. They must have what is known as a bumper (yield pad) that forms a seal to the deck. This seal can not be interrupted by any objects, like cables.
Guess that shows just how many AHJ's aren't used to working with theatres, that seems clear by the letter of the law, and I've known more than a few that allow exceptions that apparently they shouldn't.
 
Ideally, you check before house opens to ensure nothing was "added" along / under the fire line.
 
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Some theaters have a pass thru the proscenium wall. It is usually a 3 or 4" pipe with threaded caps. When not in use, its capped. When in use, pull the wires thru and stuff fire proof, not flame retardant, material in the pipe as a fire stop. Talk with your AHJ about placement and fire proof material to use.
 
Some theaters have a pass thru the proscenium wall. It is usually a 3 or 4" pipe with threaded caps. When not in use, its capped. When in use, pull the wires thru and stuff fire proof, not flame retardant, material in the pipe as a fire stop. Talk with your AHJ about placement and fire proof material to use.

They make intumescent pillows (blocks) for telecom use, I'd recommend them so you're not handling the goo each time. Unless you like red hands, red cables, red pipes...
 
NFPA 80 chapter 20 regulates fire curtains. They must have what is known as a bumper (yield pad) that forms a seal to the deck. This seal can not be interrupted by any objects, like cables.
Although the intent may be to 'seal against the stage floor', that actual wording in NFPA 80, 3.3.17 and 20.2.3 is just that the yield pad is capable of pressing against the floor. A nuanced difference, but none-the-less, it does not specifically say that there cannot be a cable laying on the floor under the yield pad. In a perfect world, we would never have this cable there. However, the reality is that there is a MUCH LARGER gap around the sides of the fire curtain where it sits in the smoke pocket, so I don't think a perfect seal is the goal. This does raise the question as to 'how much' or 'what is the maximum dimensions' of an object that does breach the bottom seal -- is it a 1/4" mic cable? A 1/2" power cord? a 1" broom handle? . . . Maybe the NFPA should add a clarifying paragraph to NFPA 80?
 
Although the intent may be to 'seal against the stage floor', that actual wording in NFPA 80, 3.3.17 and 20.2.3 is just that the yield pad is capable of pressing against the floor. A nuanced difference, but none-the-less, it does not specifically say that there cannot be a cable laying on the floor under the yield pad. In a perfect world, we would never have this cable there. However, the reality is that there is a MUCH LARGER gap around the sides of the fire curtain where it sits in the smoke pocket, so I don't think a perfect seal is the goal. This does raise the question as to 'how much' or 'what is the maximum dimensions' of an object that does breach the bottom seal -- is it a 1/4" mic cable? A 1/2" power cord? a 1" broom handle? . . . Maybe the NFPA should add a clarifying paragraph to NFPA 80?



I agree with Mr. Gilson. Nothing thru the fire line or under the fire curtain. The yield pad's function is to keep fire from burning under the curtain and to seal given undulations in the stage deck. It is not there to seal around audio, data or power cords.

T
 

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