Fred B
Senior Member
- Location
- Upstate, NY
- Occupation
- Electrician
What is the rationale for the not permitted use found in 334.12(A)(2) "Exposed within a dropped or suspended ceiling cavity.....l"
Why 334.12(A)(2) 2017 NEC
- Thread starter Fred B
- Start date
- Status
- Location
- Illinois
- Occupation
- retired electrician
That was just part of the "horse trading" when the 3 story limitation was removed from the code. There was not enough votes for removing the 3 story rule, without adding some restriction.
packersparky
Senior Member
- Location
- Wisconsin
- Occupation
- Inspector
Fred B
Senior Member
- Location
- Upstate, NY
- Occupation
- Electrician
Wish I had some reason to give to GC as to why other than because it says so. I can understand for some of those restrictions for safety reasons but not quite getting this one. How can one get access to the original proposal for this.
mbrooke
Batteries Included
- Location
- United States
- Occupation
- Technician
So no rationale was used.
That is how 95% of the code making process works. 100% Arbitrary, 0% electrical theory.
In other than Dwelling Units:
I remember a CMP member at an IAEI meeting once said it was due to concerns over being damaged due to multiple trades having easy access and tenant turnovers. He gave an example of communication contractors adding cabling and HVAC servicing and adding over periods of time, etc
I remember a CMP member at an IAEI meeting once said it was due to concerns over being damaged due to multiple trades having easy access and tenant turnovers. He gave an example of communication contractors adding cabling and HVAC servicing and adding over periods of time, etc
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
In MA, they did not adopt that section. I hear there you will find NM above a drop ceiling in say a supermarket supplying 480 three phase to a RTU. I guess these places are burning down left and right......
mbrooke
Batteries Included
- Location
- United States
- Occupation
- Technician
Most of the world wires with NYY which is basically NM but with a thicker outer jacket.
- Location
- Illinois
- Occupation
- retired electrician
Just like any other type of negotiation where you have two different view points.So no rationale was used.
You had the non-metallic wiring method supporters on one side and the metal cable jacket and metal raceway supporters on the other side. There had been a push to get rid of the 3 story rule for a number of code cycles, and this restriction to get rid of the 3 story rule was the compromise that was worked out.
You could try a PI for the 2026 code to remove that restriction.
Fred B
Senior Member
- Location
- Upstate, NY
- Occupation
- Electrician
Can't see how this could ever be allowed on it's face. They should have atleast come up with a "legitimate" safety concern to substantiate a requirement, even if it could be debated.
electrofelon
Senior Member
- Location
- Cherry Valley NY, Seattle, WA
I agree. It seems this was one of those "it seems like a good idea" codes. Never really made sense to me why aluminum MC is considered to be so godly. The stuff isn't much tougher than NM in many ways. In fact I could see some situations where it is more of a fire risk than NM.
- Location
- Illinois
- Occupation
- retired electrician
I am sure there were concerns brought up in the discussions. Not sure there were concerns that you can find in the published record. You can look at the published records for the 2002 code on the NFPA site. Not sure what exactly they will tell you.
There would be a lot to this as I recall this went to the Standards Council on an appeal, but I am not completely sure.
- Status