334.12 NM above suspended ceilings

[samson]

The 2002 NEC states in 334.12 NM can't be used in "open runs" in dropped or suspended ceilings. We ran NM through drilled 2 X 12 rafters 6" above a suspended ceiling. We did not lay or suspend any runs on the ceiling. I would think that is not an "open run" in a suspended ceiling. Am I right or wrong.

 

[luke warmwater]

Re: 334.12 NM above suspended ceilings

I've heard this argued both ways. I would like to agree with your view.
The arument that I've heard against this would require a fire barrier on the bottom of the joists that you ran through.
We've been using MC anyway.
At the most recent Code class that I attended, this didn't come up. But I will try to remember to bring it up at the next one.

 

[don_resqcapt19]

Re: 334.12 NM above suspended ceilings

The term "open run" is not defined in the code, so check with your AHJ. In my opinion, if you can see the cable, it is an "open run".
Don

 

[torint]

Re: 334.12 NM above suspended ceilings

Maybe someone can help me on this...A Master Electrician pointed these art's. that can be interpreted to allow for #12 or #14 NM to be stapled to the bottom of joist. 300.4(C)(D)(exept #2). 300.11(A)(1) 300.23 334.30(B)(1).
He said that once a drop ceiling is installed it is considered a permenant part of the structure. And that the panels are protecting the conductors from physical damage. Do any of you other guy's interprete this to be correct? I'm talking Residential.

[ April 01, 2003, 06:54 PM: Message edited by: torint ]

 

[mikeackley]

Re: 334.12 NM above suspended ceilings

torint: If the situation samson describes is in fact Residential, then that throws a different light on this discussion. Because 334.12(A)(1) as I read it does permit open-runs of NM cable in dropped or suspended ceilings in "...one- and two-family and multifamily dwellings."

[ April 01, 2003, 10:33 PM: Message edited by: mikeackley ]

 

[a.wayne3@verizon.net]

Re: 334.12 NM above suspended ceilings

In a residential installation it is permitted to run in a dropped or suspended ceiling as long as it is secured and supported as per NEC,