# "subject to physical damage"???



## bctoasters

Can anyone explain (give clear definition) what the code book means by the term "subject to physical damage"? I'm taking a 2011 code update class, and the question was brought about "clarifying" what they mean by that. I'm surprised they don't have anything in Art. 100 Definitions. After all they explain dry, damp, wet locations, etc., etc.


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## Dennis Alwon

Subject to damage is,well, subjective. It is not defined and would be difficult to define for all cases. This is usually an ahj call.


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## macmikeman

I feel it is something more or less subject to the AHJ's call. Example- some places allow exposed romex as long as its over 8' foot or thereabouts from grade while others do not allow it exposed anywhere. 

Or to boil it down, its whatever your local inspector decides "protection from physical damage" means.


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## raider1

It would be all but impossible to totally define what "Subject to physical damage" is so the NEC leaves this undefined and left up to the interpretation of the local AHJ.

Chris


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## don_resqcapt19

And my interpretation of that phase is "if you can see it, it is subject to physical damage"


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## dadtodc

I had this question a few weeks ago. I am no expert, but I do believe like the others say that it is hard to define. My question is why schedule 80 pvc for SE to a panel. All of the houses around here have schedule 40 so that what I installed , and failed inspection because I was told it needed schedule 80. I know it states that, but seems a little overkill for a 3ft riser.


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## Shockdoc

I'm still waiting for someone to swing an ax at the SE cable here on LI with it's 8' protection rule.


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## chicken steve

Gentlemen,

apparently we are in need of a test pilot ......

nominations are open....

~CS~


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## dadtodc

I am sure the cocky inspector that failed mine would try it just to show you it can bye done.


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## kbsparky

Shockdoc said:


> I'm still waiting for someone to swing an ax at the SE cable here on LI with it's 8' protection rule.


WE had a job where an exposed SE cable had been "chopped" by someone wielding an ax. I think I took a photo of the bad spot, I'll have to post it here if I can find it.

It was in the rear of a post office building, and of course they immediately lost power. I suspect that the perp got an eyeful of sparks and molten metal when he did it, and ran off in a hurry!

The PO called the POCO, and they found the bad spot in the SE cable, complete with the chop mark diagonally on the cable. 

They said nothing they could do, call an electrician to replace it.

I ended up with the task of replacing that cable -- I used PVC conduit, and ran it much higher up than the old stuff -- which was chest high.

That job took me into the night on a Friday! It even started snowing before I was finished. I'll never forget that job, for sure!!


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## macmikeman

If I can reach it, I can physically damage anything any of you fellow members could ever possibly install. That by itself is reason enough for me to call the whole thing a silly rule. Some stuff would just be a bit harder to do is all. Sometimes even cars go thru roofs of buildings...


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## rdr

Open to interpretation wouldn't always be good. If an inspector really decided to give you grief he could pretty much argue that somebody could **** up an anvil.....


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## goose134

I've seen more than a few photos here of PVC stub ups that had been shredded by weed wackers. Should it have been GRC? Totally subjective. I'm of the mind that if it's less than 8 feet off the ground, an installation will get more than its fair share of abuse. You can't a-hole proof every installation.


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## RIVETER

bctoasters said:


> Can anyone explain (give clear definition) what the code book means by the term "subject to physical damage"? I'm taking a 2011 code update class, and the question was brought about "clarifying" what they mean by that. I'm surprised they don't have anything in Art. 100 Definitions. After all they explain dry, damp, wet locations, etc., etc.


If your work can be damaged by any inadvertent contact with normal operations in the area, then extra precautions need to be done...and that is the minimum.


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## BBQ

don_resqcapt19 said:


> And my interpretation of that phase is "if you can see it, it is subject to physical damage"


What makes you believe that something that you can't see is not also subject to damage?

In many cases the fact an item is out of sight means it is more likely to be damaged.


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## BBQ

goose134 said:


> I've seen more than a few photos here of PVC stub ups that had been shredded by weed wackers.


Really?

I can't remember seeing one and I doubt a string trimmer would harm PVC.


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## Wirenuting

Protect from physical damage. 

I take that to mean "Make it Sailor proof".

I know that's almost imposable as a sailor can break or screw up anything, but it's how I try to do things.


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## Jim Port

Some of the choices to protect from physical damage also seem overboard.


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## goose134

BBQ said:


> Really?
> 
> I can't remember seeing one and I doubt a string trimmer would harm PVC.


I did a real quick search and came up with nothing. I agree a string trimmer would face an uphill battle against PVC. It may have been mower damage (as in crashing into) that I remember.


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## jmsmith

I don't believe there is any way to damage-proof anything... On an Army Corp of Engineer lock & dam project that I worked on in Peoria, Il, I watched as a mechanical contractor busted-up a brand-new supply duct bank with the outriggers on their terex. This was just a week out of the total job being done. Talk about a real letdown!!!

Sent from my iPhone using ET Forum


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## Jlarson

BBQ said:


> Really?
> 
> I can't remember seeing one and I doubt a string trimmer would harm PVC.


I've seen quite a few broken PVC stubs in well yards from idiot landscapers or operators clearing weeds with machetes and sharpened shovels. 

I still use PVC though. I'm not designing my installs to protect from idiots with large blades :no: :laughing:


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## rdr

Jlarson said:


> I've seen quite a few broken PVC stubs in well yards from idiot landscapers or operators clearing weeds with machetes and sharpened shovels.
> 
> I still use PVC though. I'm not designing my installs to protect from idiots with large blades :no: :laughing:


Idiots can always put money in your pocket. :laughing:


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## macmikeman

A simple fix for any 3/4" sched 40 out of the lawn stub up. Just go saw a 4 or 5 foot long section of sched 80 4" pvc and dig a hole in front of your 3/4" stub up. Plant that 4" in there, drop one or two lengths of #4 rebar in it, and pour a nice footing of concrete and fill the pipe up with grout as well. Let it set overnight and paint it bright yellow. Now the weed wacker guy who cuts your lawn has a bigger animal to attack so he'll leave your little bitty electrical pipe alone now..........:whistling2:


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## HARRY304E

rdr said:


> Idiots can always put money in your pocket. :laughing:


I just hope they will put money in my pocket.......:thumbup::laughing::laughing:


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## Wireman191

We did an install on 60 seasonal pickers cabins and the cabins came from Canada "Prewired" Sub panel with a big ball of MC cable you roll out and strap to the walls. All the devices were on square wooden blocks so any one could install them. Inspector said it was subject to physical damage and needed to be installed in conduit. What a mess! We lost a big costumer from that. So I guess to play it safe, if it is any type of cable below 8 feet, use conduit, seal tight, whatever so it is not and issue at the wrong time.


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## BBQ

Jlarson said:


> I've seen quite a few broken PVC stubs in well yards from idiot landscapers or operators clearing weeds with machetes and sharpened shovels.


None of those are string trimmers are they?


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## Jlarson

I was implying a string trimmer isn't gonna break PVC. Duh 

If they did I'd have broken/cut off a lot of sprinkler heads off in my time. :laughing:


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## Amish Electrician

You can 'proof' against accident, and against foolishness, but not against deliberate malice.

Temporary rant mode: The NEC is NOT the be-all and end-all of out work. That's what we sell: our SKILL. That means knowing what's appropriate fir a given situation.

"Subject to physical abuse" is a good design concept- and bad law. Unenforceable law- if for no other reason than that the need for protection becomes apparrent only long after the inspectior leaves and the job is paid for.

Nor was RMC ever intended to be the 'maximum.' You, as the professional, have a duty to recognize what is likely to happen, and what is not. You also have a number of choices available.

It's not a matter of 'legal' as much as what's smart. Those who want to play games, who want to have a different set of rules for themselves than for others, are simply dishonest.


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## brian john

kbsparky said:


> WE had a job where an exposed SE cable had been "chopped" by someone wielding an ax. I think I took a photo of the bad spot, I'll have to post it here if I can find it.


We had a job where a disgruntled ex-employee (they think) took a chain saw and cut down 3-utility poles (13.2 kv). Shut the site down. Do we put steel around all the poles?

As for “subject to physical damage” Anybody with common sense should know what it is when they see it. The problem is as my grandmother use to say “Common sense ain’t so common”.


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## rogimor

In my opinion, "subject to physical damage" Is a broad term used by the NEC. Totally covers everything that may be exposed to any I mean any physical damage. It is referring to any devices, race ways, wirings, fittings, ..etc.. in fact anything that has to do with electrical installations.


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## chicken steve

well when i was a wee lad in school, they used to sound the main alarm

and talk over the intercom

so we were all taught to crouch under our desks until the exercise was over

so for those of duck & cover vintage , we could well reminise of the days when the definition of _physical damage_ extended itself to nuke proof school desks 

i mean, they just don't make 'em like _that_ anymore......

~CS~


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## BBQ

chicken steve said:


> well when i was a wee lad in school, they used to sound the main alarm
> 
> and talk over the intercom
> 
> so we were all taught to crouch under our desks until the exercise was over
> 
> so for those of duck & cover vintage , we could well reminise of the days when the definition of _physical damage_ extended itself to nuke proof school desks
> 
> i mean, they just don't make 'em like _that_ anymore......
> 
> ~CS~


Did they teach English writing in that school? Did you sleep through it? :laughing:


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## user4818

BBQ said:


> What makes you believe that something that you can't see is not also subject to damage?
> 
> In many cases the fact an item is out of sight means it is more likely to be damaged.


Right. A buried conduit or duct bank comes to mind.


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## BBQ

Amish Electrician said:


> You can 'proof' against accident, and against foolishness, but not against deliberate malice.
> 
> Temporary rant mode: The NEC is NOT the be-all and end-all of out work. That's what we sell: our SKILL. That means knowing what's appropriate fir a given situation.
> 
> "Subject to physical abuse" is a good design concept- and bad law. Unenforceable law- if for no other reason than that the need for protection becomes apparrent only long after the inspectior leaves and the job is paid for.
> 
> Nor was RMC ever intended to be the 'maximum.' You, as the professional, have a duty to recognize what is likely to happen, and what is not. You also have a number of choices available.


I think if you talked to the people who make the code they would agree with you. 

The problem is they have to write a code section that the inspector can use when the person doing the work is just a moron and is not doing the right thing.

I am willing to bet they leave it written the way it is so the AHJ / Inspector has some discretion. You and I both know that in one case EMT is enough and in another case we better run rigid but if we tried to write a concise code section describing it well for every situation and we would have a lot of trouble.

So while I certainly agree it is not perfect as is I prefer this vagueness over 'mandatory RMC' every time type code sections.

I think it pays to talk to the inspector ahead of time.


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## chicken steve

BBQ said:


> Did they teach English writing in that school? Did you sleep through it? :laughing:


i have little time for the vernacular challenged BBQ

~CS~


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## BBQ

Peter D said:


> Right. A buried conduit or duct bank comes to mind.


Wiring in walls & ceilings hit by drills and sawzalls, if they had seen the wiring they would not have hit it.


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## BBQ

chicken steve said:


> i have little time for the vernacular challenged BBQ
> 
> ~CS~





If it was only as clever as you think it is. :laughing:


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## user4818

BBQ said:


> Wiring in walls & ceilings hit by drills and sawzalls, if they had seen the wiring they would not have hit it.


Yeah, that too.


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## jmsmith

There are times when you can do right, even to the point of overkill... But that does not cure "idiot-proof"!
:blink:

Sent from my iPhone using ET Forum


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## B4T

BBQ said:


> Really?
> 
> I can't remember seeing one and I doubt a string trimmer would harm PVC.


I agree.. the 4X4 that holds the swimming pool controls get beat to death by landscapers and I have never seen one cut or broken..

But the 4X4 has rounded corners at grade level..


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## RAHARRIS78

When it comes to a matter of interpretation you lose.Get use to it.


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## rogimor

BBQ said:


> I think if you talked to the people who make the code they would agree with you.
> 
> The problem is they have to write a code section that the inspector can use when the person doing the work is just a moron and is not doing the right thing.
> 
> I am willing to bet they leave it written the way it is so the AHJ / Inspector has some discretion. You and I both know that in one case EMT is enough and in another case we better run rigid but if we tried to write a concise code section describing it well for every situation and we would have a lot of trouble.
> 
> So while I certainly agree it is not perfect as is I prefer this vagueness over 'mandatory RMC' every time type code sections.
> 
> I think it pays to talk to the inspector ahead of time.


 

I gree, I want room for improvement, I do not want to memorize the code book.


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## brian john

RAHARRIS78 said:


> When it comes to a matter of interpretation you lose.Get use to it.


If you are talking about inspectors, it depends on your knowledge and if the inspector is willing to learn or is pig headed.

I have educated a few and had just as many ignore me.


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