110.26(C)(2) ? 2011 NEC

[charlie b]

If an electrical room has one switchboard that meets the requirements (over 1200 amps and over 6 feet wide), and if I wish to apply sub article (a), do I only have to show an unobstructed path from that switchboard?s working space to the room?s only exit, or do I also have to show an unobstructed path from the working space of every other panel in the room to the room?s only exit?

 

[texie]

If an electrical room has one switchboard that meets the requirements (over 1200 amps and over 6 feet wide), and if I wish to apply sub article (a), do I only have to show an unobstructed path from that switchboard?s working space to the room?s only exit, or do I also have to show an unobstructed path from the working space of every other panel in the room to the room?s only exit?

I just had this issue as well on a job recently. Applying the (a) or (b) exception has always been hard for me to apply without help. I have found the NEC Handbook has some pretty good figures and commentary to help apply these rules. See pages 58 and 59 in the 2011 version or pages 56 and 57 in the 2008 version.

 

[Gregg Harris]

If an electrical room has one switchboard that meets the requirements (over 1200 amps and over 6 feet wide), and if I wish to apply sub article (a), do I only have to show an unobstructed path from that switchboard?s working space to the room?s only exit, or do I also have to show an unobstructed path from the working space of every other panel in the room to the room?s only exit?

I would interpret it to be from the work space of the 1200 amp equipment to the means of egress

 

[charlie b]

Another twist to this (rapidly developing) story: If I have a 2000 amp board that is just over 6 feet wide, and that has three vertical sections each of which is about 2 feet wide, does 110.26(C)(2)(a) require me to treat the working space in front of the left hand section as interfering with an unobstructed path between the working space of the right hand section and the door?

 

[david luchini]

Another twist to this (rapidly developing) story: If I have a 2000 amp board that is just over 6 feet wide, and that has three vertical sections each of which is about 2 feet wide, does 110.26(C)(2)(a) require me to treat the working space in front of the left hand section as interfering with an unobstructed path between the working space of the right hand section and the door?

I wouldn't consider each vertical section as having its own working space, I would consider the entire switchboard to have one working space.

Disirregardless of that, I don't see how working space could be considered an obstruction.

 

[GoldDigger]

:thumbsup:
Looking at it another way, the duty to keep the working space free of obstructions does not mean that you cannot stand in it. Well for most people anyway.

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