Working Clearance NEC 110.26(C)(2)(a)

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Geon_W

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This section of the code allows for a single entrance to a working space with large equipment (rated over 1200A) if there is a continuous and unobstructed way of exit travel.

My question is whether this single entrance/exit has to be directly infront of the large equipment ?
 
The entrance does not have to be directly in front of the electrical equipment. Per section 110.26(C)(2)(a) it has to be continuous and unobstructed. An example of a violation would be the electric equipment positioned in a room where working space would be behind the equipment where you could be trapped between the equipment and the exit door.
 
You can go thru the work space but you can't have the equipment be located between you and the exit where you could be trapped. For example if the electrial equipment were against the wall and the working space was in front you could pass thru to the exit.
 
In case of a hazard one would need to get out of the working space (harzadous area) and then make their way to the exit. If you have to go thru the working space to get to the exit then one would be trapped.
 
Working space is not intended to be the "hazard limit." It is not a matter of your being at risk while in the space, and being safe once you are out of the space. That is not its intent. The presumption is that you are inside the working space, actually working, when an event occurs. You need to be able to get to a door. You must certainly be walking through the working space in which you are standing, to get to a door.

My notion of a violation of this rule would be if as you stand in front of the equipment, with the one and only exit door to your right, and if in order to get access to the inside of the panel the door that you need to open is hinged on its right side. Thus, with the panel door open, the door is now located between you and the exit door. I would call that "obstructed."

It is worth noting that the rules changed with the 2008 NEC.
 
For the most part I agree with Charile, but would like to point out that the "double working space option" does allow the door to be on one side of the room.

Steve
 
The illustration in the NEC seems to define continous and unobstructed exit as walking away from the large equipment and not past it. This interpretation seems to mean that if you have to walk past the large equipment to get to the exit then you have to have double the working clearance.
 
steve66 said:
For the most part I agree with Charile, but would like to point out that the "double working space option" does allow the door to be on one side of the room.
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I don't think we are seeing this differently. But I might have explained my point less clearly than I had hoped.

I have no problem with the room door being to the side of the equipment, with or without the double distance. I do have a problem if the panel access door will be between the worker and the room door, when the panel access door swings open. I mean that the panel access door can itself be an obstruction that prevents our use of that particular exception.
 
As Charlie said do the panel doors open and create an obstruction? If they don't what would be the obstruction?
 
SEO said:
As Charlie said do the panel doors open and create an obstruction? If they don't what would be the obstruction?
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My point is that if there is a hazard, arcing or a flame infront of the switchboard. The flame would obstruct the exit, making it impossible for one to get out of the room.
 
Looking at your drawing I see your point. An arcing event could obstruct your exit. So IMO per your drawing you would have to double the work space or install an additional exit door.
 
Geon_W said:
My point is that if there is a hazard, arcing or a flame infront of the switchboard. The flame would obstruct the exit, making it impossible for one to get out of the room.
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SEO said:
Looking at your drawing I see your point. An arcing event could obstruct your exit. So IMO per your drawing you would have to double the work space or install an additional exit door.
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I agree with both of these gentlemen.
This scenario would require more space between the opposing pieces of equipment.
 
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