310.15(B)(2)(c) (Ripped from another forum)

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rbalex

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Permit me to muddy the waters even further. But first, I agree with Don; it would have been far preferable to have used ?code? (raceway)rather than ?field? (conduit) language.

There may be general agreement that all (electrical) conduits are raceways, but not all (electrical) raceways are conduits; but is that necessarily true?

The current (2008) definition of raceway lists one form of ?conduit? (RNC) that no longer exists, and one (liquidtight flexible conduit) that technically never did, since both LFMC and LFNC were already separately recognized when the original ?list? of raceways was incorporated into the definition in 1996. In fact, of the nine (9) current conduit types specifically recognized in Chapter 3, only three (3) are actually listed in the current definition of raceway: IMC, FMC and RMC. Lest anyone point out that PVC and RTRC are called RNC, I am aware of it; I?ll also point out HDPE is not.

Nevertheless, the definition does recognize the list is not necessarily all inclusive, so it is reasonable to include the other five types because they still fit the root definition.

The crux of the problem then is, ?what is ?code? language?? in this case since raceway is a defined term, but conduit is not.

Those who have been around here long enough have heard me say that the second sentence of 90.4 is a statement of responsibility rather than a free grant of prerogative to the AHJ; i.e., the responsibility is to interpret, not make code.

But interpret still cuts a broad swath. The NFPA Manual of Style declares Webster?s Collegiate Dictionary, 11th edition to be the authority of a word?s meaning in an NFPA Standard in absence of a definition within the Standard.

According to Webster?s interpret?s basic definition is, ?to explain or tell the meaning of.? Only the most obstinate would deny part of that would be to determine intent if it may otherwise be unclear. In addition, the relevant definition of conduit is, ?a pipe, tube, or tile for protecting electric wires or cables.? According to this definition all raceways (and maybe a few more things) are conduits. Note: Neither tube nor cylinder necessarily imply a circular cross section.

In my opinion, an AHJ using common and standard rules of interpretation could readily arrive at the fact that EMT is indeed a conduit and 310.15(B)(2)(c) applies.

This doesn?t mean I like 310.15(B)(2)(c); I don?t. It was based on well meaning but scientifically unverifiable experiments with no apparent peer review or replication. While no more ?scientific,? CMP member McClung was right on, when he said industry?s combined experience refuted the Proposals Substantiation. Unfortunately, the panel members that voted for it stood to make a nickel.
 

iwire

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If an AHJ can decide that conduit means tubing to me that means the NEC is next to worthless.

So the EC follows the code as written and then at inspection the AHJ interprets conduit as tubing ..... that is just unfair.
 

Twoskinsoneman

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If an AHJ can decide that conduit means tubing to me that means the NEC is next to worthless.

So the EC follows the code as written and then at inspection the AHJ interprets conduit as tubing ..... that is just unfair.

The AHJ isn't making up definitions. The definition is easily found in any dictionary. Why are you trying to make the word "conduit" into specific raceways that have the word conduit in the title?

iwire this is my specific question... Why don't you accept the common definition of the word since it is not defined by the nec? (article 100)
 

iwire

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iwire this is my specific question... Why don't you accept the common definition of the word since it is not defined by the nec? (article 100)

IMO it is defined in the NEC numerous times by inference, all the 'scopes' you asked about and for another example

benaround said:
I would have to say EMT does not apply in 310.15(B)(2)(c), To back that up I would

refer you to 310.15(B)(2)(b) , that is right above it in the NEC, it says "more than one

Conduit,Tube, or Raceway".

Don explained it well and I fully agree with his post.


This is just another example of the CMP using "field language" when they should be using "code language". EMT is conduit in "field language" but it is not conduit in code language. The enforceable rule is in the code and code language applies, EMT is not covered by this rule. I am sure that they intended it to be covered, but they did not use the correct wording to cover it.
 

George Stolz

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If an AHJ can decide that conduit means tubing to me that means the NEC is next to worthless.

So the EC follows the code as written and then at inspection the AHJ interprets conduit as tubing ..... that is just unfair.
I just think it's an occasion where it's likely that the inspector is invariably going to apply "common sense" in applying the section, instead of blindly following the actual language. I realize it's not a perfect situation, but it doesn't bum me out too much. If the wording sticks long enough without correction to garner a "language used successfully for years" reply to an attempt to correct it, that is when my ulcer will start acting up. ;)

I mean, do you lose sleep at night about the fact that attempts have been made repeatedly (and failed) to remedy the language in 310.4 regarding parallel conductors? To compare the two, it's exactly like getting all worked up when attempting to install two 12 AWG conductors in parallel and getting cited for it, even though the language does not prohibit it.

Between the two sections, 310.4 draws my ire more than this one. Know what I mean? :)
 

M. D.

Senior Member
To me,.. by definition,.. EMT is a conduit. If the CMP wants to exclude it they can ,..I doubt they will,... since the copper selling folks included it in those tests they did in Nevada :smile:
 

iwire

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Massachusetts
Well I am not losing any sleep over this but to me it is crystal clear that the NEC language is not being used correctly. The fact that both Don and Bob A see it that way as well just makes me sleep all the better.


And still no one has replied to my question about wire ways on roofs, are they also conduit?

How about if I run parking deck MC across a roof is that also now conduit?


The wording is wrong, it should be fixed and I am sure it will be.
 
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