Definitions: Secured vs. Supported

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George Stolz

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1.) NEC Section/Paragraph: Article 100
2.) Proposal Recommends: [new text]
3.) Proposal: Add the following definitions to article 100:
Secured. Fastened to a structure or framing member by an approved means.

Supported. Resting either in a hole in a framing member or on top of a framing member, using only gravity to maintain the location of the installation.


4.) Substantiation: The cable articles of chapter three of the 2005 NEC use the two terms interchangeably, where they are generally interpreted to describe two distinct principles of installation.

As currently worded, the articles imply that the weight of a cable resting on a structural member is not supported unless it involves a fastening means (see 334.30, 332.30, 320.30). Given the reliable nature of gravity, it is generally accepted that cable supported by framing members will not float away or place undue stress at points at which it is fastened.
__________________________________________________
Am I a smartass or what?

When I started writing this, I took it for granted that the terms were used interchangably all over. In further research, I only found 320.30, 332.30, and 334.30 muddying things up.

I view supporting as using the existing structure to bear the weight of the installation. Without support, the weight of the installation would tear itself apart. In situations where the weight is borne onto the structure, securing it to the structure that's supporting it is silly. Gravity won't reverse itself, and if it did ( :D
 

petersonra

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engineer
Re: Definitions: Secured vs. Supported

I don't like this. It seems to imply you could for instance just lay a cable on top of a 2X4 the length of the structure without tacking it to the 2X4 at all.

I don't have a problem with going through a hole in a 2X4 not requiring a staple, but I don't like the idea of laying 100 foot of Romex on top of a 2x4 without stapling it periodically.
 

George Stolz

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Re: Definitions: Secured vs. Supported

Huh? :D

I think Bob is thinking of NM run with the running board, and forgetting about NM run perpendicular to the running board. ;)
 

petersonra

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Northern illinois
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engineer
Re: Definitions: Secured vs. Supported

I don't like the idea of just laying Romex on top of a board parallel to the floor with out stpling it to the board. Otherwise it could come off the board and be unsupported.
 

rbalex

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Re: Definitions: Secured vs. Supported

At this point we are trying to help develop the Proposals for submittal - not to attempt to discourage submitting them. We want Proposals that are not rejected "out-of-hand" for non-compliant style rather than content. We'll get to our objections at the "Comment" stage, if necessary.

This is important because it helps create an CMP documented response for our industry's common reference, whether we "like" a Proposal or not.

[ May 02, 2005, 11:55 AM: Message edited by: rbalex ]
 

rbalex

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Re: Definitions: Secured vs. Supported

Now for my comment. :D George are you planning to submit Proposals to "un-muddy" 320.30, 332.30, and 334.30. If so, SAY SO (and do it ;) ).

Did you consider [2005] 590.4(J)?

You may also be interested in the following Proposal in the NFPA 70 ? May 2001 ROP as a precedent even though it was rejected. Consider ?support? in un-trafficked areas in light of the CMP Statement.
(Italics mine)

3- 133 - (305-4(j), Exception (New) ): Reject
SUBMITTER: Dan Leaf, Palmdale, CA
RECOMMENDATION: Add an exception to read as follows:
Exception: Flexible cords approved for hard usage shall be permitted to be run on the ground or floor where they are not likely to be damaged and where there is no available structure to provide support, or where they are suitably protected against damage.
SUBSTANTIATION: This proposal simply reflects the real world use, and provides for the period when there is no available structure to provide support or where no actual structure is erected. It allows for judgement and is in line with the panel statement for Comment 3-149 in the 1998 ROC that the text of Section 305-4(h) does not prohibit cords run on the floor provided they are adequately protected. It would be helpful to Code users to be aware of that. Protection can be afforded by location or physical means. Section 525-13(f) doesn?t prohibit flexible cords run on the ground and only requires physical protection where accessible to the public.
PANEL ACTION: Reject.
PANEL STATEMENT: There is no restriction on the use of hard usage flexible cords where they are not likely to be damaged so the exception is not necessary. If they are temporarily run on the floor and not subject to physical abuse, they are supported by the floor and no further support is necessary.
NUMBER OF PANEL MEMBERS ELIGIBLE TO VOTE: 11
VOTE ON PANEL ACTION:
AFFIRMATIVE: 11
COMMENT ON AFFIRMATIVE:
CASPARRO: Section 305-4(h) requires that flexible cords and cables be protected from physical damage. I disagree with the Panel Statement that cords can be supported by the floor. It is difficult to understand how laying conductors on the floor would not be subjected to physical damage. OSHA 1926.405(a)(2)(ii)(B) prohibits branch circuit conductors from being installed on the floor.

[ May 03, 2005, 09:07 AM: Message edited by: rbalex ]
 

George Stolz

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Windsor, CO NEC: 2017
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Re: Definitions: Secured vs. Supported

Yeah, I had the mental steam to throw this out there, and then lost it when it came time to work up the coordinating proposals.

Mr. Alexander (only because everybody's Bob around here), thanks for the ROC. That is encouraging. :)
At this point we are trying to help develop the Proposals for submittal - not to attempt to discourage submitting them.
Hey, the discouragements help mold the finished product, I don't mind at all. ;)
I don't like the idea of just laying Romex on top of a board parallel to the floor with out stpling it to the board. Otherwise it could come off the board and be unsupported.
I think this would be better addressed in the individual articles, don't you agree?
 
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