NM in suspended ceilings

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Im guessing it was allowed. I live in Maryland and a commercial resturant that im working on is full of nm and the ceiling used to be a drop. They have since removed the drop ceiling. The code says that you cant even have nm above a drop ceiling since it is still accesable. The inspector dosent seem to have a problem with it because it was already thier.
 
lawrence kany said:
Has NM cable ever been allowed to used in suspended ceilings of commercial buildings
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Sure, NM is still allowed in commercial buildings although now above suspended ceilings is prohibited.
 
It's sort of a tug of war between EMT guys and NM guys, they finally allowed NM in buildings over 3 stories, but they added the "not allowed over drop ceiling rule" which makes no sense to me by the way... :grin:
 
FWIW, I was under the impression that the reason that nm is not allowed in dropped ceilings is due to the toxic smoke development of the pvc jacket during a fire.
 
nakulak said:
FWIW, I was under the impression that the reason that nm is not allowed in dropped ceilings is due to the toxic smoke development of the pvc jacket during a fire.
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What about the rest of the stuff in the building? And at that point the fire is pretty out of control wouldn't you say?
 
nakulak said:
FWIW, I was under the impression that the reason that nm is not allowed in dropped ceilings is due to the toxic smoke development of the pvc jacket during a fire.
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That is the case with air handling ceilings.

But for non air handling ceilings it was literally a trade off for the removal of the 3 story restriction.
 
iwire said:
Kind of, but more directly 300.22(C)(1) does not list NM as a wiring method for those above ceiling spaces.
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Thanks, I did not know there was a code that direcly addressed it, but it would make sense that NM would be forbidden.
 
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