NEC Handbook Commentary 180

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steve66

steve66

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Although the code text for 700.10(D)(1) seems to basically state the same thing in both the 2011 NEC and the 2017 NEC, the handbook commentary has made a 180 degree turn. The new commentary states the exact opposite of the 2011 commentary.

The basic rule is that certain emergency feeders need to be installed in spaces or areas that are fully protected by a fire suppression system.

In the 2011 Handbook commentary, buildings that were fully sprinklered complied with the requirement. Fully sprinklered buildings do not normally have sprinklers above suspended ceilings, since there are not usually any combustibles above the ceiling. I believe it is a standard exception in the sprinkler code. Not sure i have ever seen sprinklers above a ceiling.

According to the new 2017 Commentary, sprinklers have to be provided above the ceiling if the feeder is above the ceiling.

Why the change? Does this mean the old commentary was wrong? Are sprinklers required above the ceiling even if a building is completely sprinklered?

View attachment 2011 NEC.pdf

View attachment NEC 2017.pdf
 
steve66 said:
Although the code text for 700.10(D)(1) seems to basically state the same thing in both the 2011 NEC and the 2017 NEC, the handbook commentary has made a 180 degree turn. The new commentary states the exact opposite of the 2011 commentary.

The basic rule is that certain emergency feeders need to be installed in spaces or areas that are fully protected by a fire suppression system.

In the 2011 Handbook commentary, buildings that were fully sprinklered complied with the requirement. Fully sprinklered buildings do not normally have sprinklers above suspended ceilings, since there are not usually any combustibles above the ceiling. I believe it is a standard exception in the sprinkler code. Not sure i have ever seen sprinklers above a ceiling.

According to the new 2017 Commentary, sprinklers have to be provided above the ceiling if the feeder is above the ceiling.

Why the change? Does this mean the old commentary was wrong? Are sprinklers required above the ceiling even if a building is completely sprinklered?

View attachment 21664

View attachment 21665
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If you have a room (or corridor) with a suspended ceilng, isn't there two spaces? One above the ceiling and one below? I have seen sprinklers above a suspended ceiling.
 
The code language in both editions, requires that the space where the feeder circuit is installed be protected by an approved automatic fire suppression system. It seems very clear to me that the actual space where the feeder is being installed must be protected.

Remember the comments in the handbook are not code and are not an official position or interpretation of the code language.
The commentary and supplementary materials in this handbook are not a part of the NFPA Document and do not constitute Formal Interpretations of the NFPA (which can be
obtained only through requests processed by the responsible technical committees in accordance with the published procedures of the NFPA). The commentary and supplementary
materials, therefore, solely reflect the personal opinions of the editor or other contributors and do not necessarily represent the official position of the NFPA or its technical committees.
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It would be interesting to see if the editors for the two editions were the same.
 
I would agree if the code section only said "spaces". Below the ceiling is one space, above is another.

However, the code section says "spaces or areas". It seems very likely that an "area" was meant to be an "area" of a building. Or even an entire building.

And if the "area" or the entire building is fully covered with fire suppression per NFPA 13, it would seem like the requirement has been met.
 
steve66 said:
I would agree if the code section only said "spaces". Below the ceiling is one space, above is another.

However, the code section says "spaces or areas". It seems very likely that an "area" was meant to be an "area" of a building. Or even an entire building.

And if the "area" or the entire building is fully covered with fire suppression per NFPA 13, it would seem like the requirement has been met.
Click to expand...

To me the "area" above a suspended ceiling and the "space" above a suspended ceiling are the same thing.
 
packersparky said:
To me the "area" above a suspended ceiling and the "space" above a suspended ceiling are the same thing.
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The code typically isn't redundant when it doesn't have to be. If area and space were meant to mean the same thing, I don't thing they would have said area or space.
 
steve66 said:
I would agree if the code section only said "spaces". Below the ceiling is one space, above is another.

However, the code section says "spaces or areas". It seems very likely that an "area" was meant to be an "area" of a building. Or even an entire building.

And if the "area" or the entire building is fully covered with fire suppression per NFPA 13, it would seem like the requirement has been met.
Click to expand...

I read "area" as being a subset of a "space", and a space as being bounded on all sides...especially when juxtaposed with 700.10(D)(2) where the "space" has to either be fully protected or the space has to have a 2-hr fire resistance rating.

I think this would allow the feeder circuit to pass through a large space, and have only the portion of the space that the feeder passes through (the area) to be protected.
 
I was looking at it the other way - an area is a larger volume that could include both the space below and above the ceiling.

At any rate, I believe the sprinkler code still states that an area can be "fully protected" even if sprinklers are specifically in that area. For example, an entire building can be fully protected even if spaces above ceilings and elevator shafts don't have coverage.

It seems vague at the least, especially given the conflicting commentaries. I was considering asking for an official interpretation.
 
Another place that leaves me wondering what is correct: The 2015 NFPA 99 specifically excludes these paragraphs from health care facilities:

Code: 
[COLOR=#000000][FONT='inherit'][B]6.4.2.2.1.5 [/B][/FONT][/COLOR][SIZE=2][COLOR=#000000][FONT='inherit']For the purposes of this code, the provisions for emergency systems in Article 700 of [I]NFPA 70[/I], 
[I]National Electrical Code[/I], shall be applied only to the life safety branch.
[B]6.4.2.2.1.6 [/B] The following portions of Article 700 of [I]NFPA 70[/I] shall be amended as follows:
[B](A) [/B] 700.4 shall not apply.[/FONT][/COLOR]
[COLOR=#000000][FONT='inherit'][B](B) [/B][/FONT][/COLOR][COLOR=#FF0000][FONT='inherit']700.10(D)(1) through (3) shall not apply.[/FONT][/COLOR][/SIZE]

So no special fire protective means are necessary for emergency feeders in a hospital? Is that right?

I really wonder if they meant to say "700.10(D)(1)(1) through (D)(1)(3) shall not apply."? Then instead of eliminating the requirement for fire protection, they would be eliminating some methods of fire protecion, leaving only (D)(1)(4) which is a cable or raceway protected by a listed 2 hour fire rated assembly, or (D)(1)(5) which is encasement in concrete. Protection by sprinklers would not be enough.

Also, the 2017 NEC has added some health care occupancies to the very same requirement that NFPA 99 says are exempt:

2017 NEC - 700.10(D)(3) Health care occupancies where persons are not capable of self preservation.

So I'm at a total loss to what the requirements have been, what they are now, and what they are going to be in the future.
 
steve66 said:
At any rate, I believe the sprinkler code still states that an area can be "fully protected" even if sprinklers are specifically in that area. For example, an entire building can be fully protected even if spaces above ceilings and elevator shafts don't have coverage.
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I'm not sure that the sprinkler code uses the terms fully protected or fully sprinklered. But I certainly don't wish to read all of NFPA 13.
 
steve66 said:
I was looking at it the other way - an area is a larger volume that could include both the space below and above the ceiling.

At any rate, I believe the sprinkler code still states that an area can be "fully protected" even if sprinklers are specifically in that area. For example, an entire building can be fully protected even if spaces above ceilings and elevator shafts don't have coverage.

It seems vague at the least, especially given the conflicting commentaries. I was considering asking for an official interpretation.
Click to expand...

If an "area" included any "space" within that "area" there would be no need for the code to say "space". IMO the code is saying that where an emergency feeder is in a space such as above a suspended ceiling, additional protection for the feeder is required.
 
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