Physical Damage

[sfordsr]

I have been informed by an inspector that MC cable cannot be used in a garage or sunroom that is to remain as open studs. The inspector cited 330.12(1) - Uses Not Permitted. It states it cannot be used "where subject to physical damage".
Note that this statement also appears in the sections for FMC, LFMC, PCV, LFNC, and even EMT ("where subject to severe physical damage), and probably other areas.
Can someone please tell me the definition of this statement "subject to physical damage"?

 

[augie47]

Welcome to the forum.

Unfortunately, I think you will find it to be a AHJ amendment call.
I'm unsure what percentage of inspectors would permit such an install.
MC spanning an area between studs would not withstand much pressure from persons pulling on it or from items striking it.
I would tend to agree with the call.

 

[suemarkp]

Is there any reason you didn't use NM cable? It has the same restrictions. To me, MC cable and flex conduit seem more damage tolerant than NM cable, but there is no decent definition of physical damage.

You may be able to nail a fence board or similarly sized board on the wall to protect the cable from damge. Some may allow cable above a certain height to be exposed. In that case, using EMT stubs out the top of each device box would be fairly easy to do. Otherwise, sheetrock or panel the wall.

 

[e57]

Can someone please tell me the definition of this statement "subject to physical damage"?

It is whatever the AHJ feels it might be...

Example from SF Electrical code... (Where MC also is not allowed uncovered by finish or protection below 8')

Subject to Physical Damage. Wiring installed
within 2.44 m (8 feet) of a walking surface or
finished floor is considered subject to physical​

damage.

 

[cpal]

I have been informed by an inspector that MC cable cannot be used in a garage or sunroom that is to remain as open studs. The inspector cited 330.12(1) - Uses Not Permitted. It states it cannot be used "where subject to physical damage".

Well it's difficult to have an opinion on your installation without viewing it. But you must keep in mind that virtually all of the wiring methods are restricted from use where they will be damaged. I like to think that the restrictive language applies to intended use after project completion. But the Code is not a design manual. Actually BX and MC have the exact same language. Will the AHJ allow BX?

Let us know I for one am interested

 

[nakulak]

sunroom with open studs ? that sounds ugly. conceal it, problem solved.
garage ? - I agree. ask him if EMT is ok, or run surface wiremould ? or emt ?

 

[Hendrix]

As long as you run parallel to the framing members and above 8' on a resi. instalation, I would allow NMB.

 

[don_resqcapt19]

My definition of "subject to physical damage" is very simple...if you can see it, it is subject to physical damage. As the others have said this is a very subjective code rule and you will fine many different definitions, but none more restrictive than mine:grin: I don't have one for "subject to sever physical damage".

 

[macmikeman]

Don't worry, none of the wiring in either pic was damaged. You couldn't see any of it after it was installed....:grin:

 

[peter d]

That care must have been going mighty fast to end up through a roof.

 

[LarryFine]

That care must have been going mighty fast to end up through a roof.

Backwards, no less.

 

[jaylectricity]

sunroom with open studs ? that sounds ugly. conceal it, problem solved.
garage ? - I agree. ask him if EMT is ok, or run surface wiremould ? or emt ?

Which one is better? EMT? Or emt?

 

[peter d]

Which one is better? EMT? Or emt?

Or eMt?

 

[Ragin Cajun]

Backwards, no less.

Don't think so. The roof is peeled out from the right to the left. I would say the car cane right to left. And, yes, you can bet he was "flying"!

RC

 

[LarryFine]

Don't think so. The roof is peeled out from the right to the left. I would say the car cane right to left.

My forensics "spider sense" tells me that there would be building material on the hood and entire roof of the car, as well as ahead of the front wheels and bumper, if you were correct.

The little bit of debris atop the rear of the roof of the car could simply be from the sheathing and roofing rotating somewhat like a cantilever around the edge of the hole.