ECN Forum Forums Code Related Discussion NEC & other Code issues 110.26 C Clearences

Greg:
Yes, you are correct that the wording within the NEC is vague, on a situation like this thread.

I stated that my comments were 'my opinion', and based on the def within Article 100.

As I do not believe the described conditions in this thread are 'common', I think the proposal would be rejected.

Having an egress path that can be utilized to 'escape' is the concern, and in my opinion the intent of 110.26 et al.

The alternative to my decision here in NJ would be for the Design Professional or EC appealing my decision to the County Board of Appeals.

If you look at article 100 you get all the way to "readily accessible" before they prohibit a portable ladder.

Greg:
Accessible (as applied to equipment) and the key word 'elevation'

I realize that some (or all) may think I'm standing on thin ice, but this would be my stand.

Yoop should have a chat with the local AHJ in his area, and see how he feels on this.

I read elevation in that regard as responding to the reach height of the equipment as in 240.24(A)



Note that even that says "above the floor or working platform"

I would really like to see what NFPA is thinking here.

IIRC, the idea of installing false floors above conductors -- even fuses -- goes all the way back to Edison -- as in day one.

This topology is still used in data centers.

I suspect it was the quick and cheap way out when rail roads were electrified.

Such language as "working platform" would seem to have been dropped in to cover just such switching schemes.

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I go back to my original comment: Such a matter as this is normally decided entirely outside the NEC. The AHJ is the Fire Marshall. His concerns turn on what the responding crews will have to face when it comes time to de-energize a flaming, smoking building.

Strictly speaking, there are no electrical considerations, in the most direct sense, at issue.

No matter how straight forward a given installation may appear -- there's always a bigger idiot out there to break a fool-proof system.

Such discoveries make for Code revisions about every three-years.

Guys
As you know theses are the kinda questions you want to know the answer before the AHJ arrives.
I feel if its an Electrical room enclosed the two door same level applies. If (a) (b) do not come into play.
If its an open platform area .
Well then all bets are off.
As then just clearances come into play.
The job this apply's to is quite large , we have at least 15 to 20 large mcc & HV rooms
I agree this is an unclear area in the Code .
Again Thus my Question.
Yoopersup

I guess Yoop agrees with me...

"I feel if its an Electrical room enclosed the two door same level applies. If (a) (b) do not come into play."

I have an open platform job in plan review as we speak. 2500 amp, 277/480, with a gen tap box outside on another platform. Clearances were worked out.

Platform is necessary to get the new gear above BFE. (Base Flood Elevation) This is the first of three services at this complex.

I guess it is time for a better description of the area we are talking about.
Is it enclosed on all 4 sides? Where is the ladder? How would you eliminate the ladder if there is no floor on the other side at that elevation?

Do they really have to move the equipment to another location?

I think you are going to need language that is far less ambiguous than anything I have seen so far to address this.

Greg:
Yoop didn't say if he has to install something within the 'existing' room, or what scope of work he is involved with.

Over the last few years, a lot of new gear has been retrofitted into existing e-rooms here. A lot was replacement gear from Sandy flooding. There were no issues with modifications to any of the -rooms. Change of door swing, panic hardware, relocating doors/walls, installing e-lites, etc. Most of the jobs fortunately had the ability to make the mods without major work.

One in particular required bumping into the warehouse space to enlarge the e-room. Block wall bump-in, steel decking for ceiling & 2 new egress doors.

IMHO, Yoop may be between a rock & a hard place. I still think he should talk to the local AHJ first.