Concrete Pad Obstruction in Workspace Clearance?

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cvirgil467

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I usually see floor mounted electrical equipment (switchboards, transformers, generators, etc) installed on concrete pads and the concrete pad usually sticks out beyond the equipment by a few inches. In some cases by a few feet.

If the concrete pad (let's say 4" high) extends 2'-0" in front of the equipment that needs to be accessed, would this be considered an obstruction to the workspace clearance required by Table 110.26(A)(1)? Or is the code silent on elevation changes in the workspace clearances?

Thanks.
c
 
I have had inspectors and facility safety people call this out if the pad was more than a few inches bigger than the foot print of the equipment, one solution was to increase the size of the pad to the minimum required clearance.

Roger
 
I would have a hard time drawing a line on the maximum distance the pad can extend beyond the equipment. I would say that 4" is fine, that 6" is starting to get not-so-fine, and that 2 feet is definitely too much. The issue is whether a future worker would try to stand on the pad, rather than on the floor below the pad, in order to work on the equipment. At 2 feet, a worker may well try to stand on the pad, which would make it a hazard should he or she take a half step backwards. They could start to fall back, and might grab anything nearby to prevent a fall. That "anything nearby" might just be the wrong thing.
 
I don't see any 4" high pad as an obstruction to working on a piece of equipment. We have have pads of all different size extensions from 2" to 2' and it never seemed to make much of a difference.
 
I think the height of the pad means nothing. But if you are standing on the pad, while working on the panel, then you need the full 3 feet (or more, depending on voltage level) to stand upon. Else you risk tripping. But if you can stand on the floor, not on the pad, and be close enough to the panel to be able to reach in easily, then the pad would not be an obstruction.
 
cvirgil467 said:
I usually see floor mounted electrical equipment (switchboards, transformers, generators, etc) installed on concrete pads and the concrete pad usually sticks out beyond the equipment by a few inches. In some cases by a few feet.

If the concrete pad (let's say 4" high) extends 2'-0" in front of the equipment that needs to be accessed, would this be considered an obstruction to the workspace clearance required by Table 110.26(A)(1)? Or is the code silent on elevation changes in the workspace clearances?

Thanks.
c
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110.26(A) is not the relevant section, 110.26(F) is. Nothing non electrical in the dedicated equipment space. If a couple of inches of concrete stick out past the gear that may be tolerable to most reasonable people. Once it's a pad big enough to stand on it needs to meet full workspace dimensions.
 
I think that 110.26(A)(3) is the correct code section. There were a number of PIs submitted for the 2020 code that would specifically permit a house keeping pad to extend out 4 to 6" in front of the face of the equipment.
 
One of the issues not mentioned is that if you are using something like a Hilti-type system to secure the equipment directly, or a Unistrut frame, to the pad there is a minimum clearance from the edge of the hole to the edge of the pad that must be observed.
 
The raised concrete pad is either in or not in the workspace, correct? If it's technically in the workspace, however you would not have to stand on it, then technically it's still a violation, no?

The NEC does not differentiate between violations, from it's technically wrong but will work fine, from it may work fine but it may be unsafe, to if you wire this way you're going to kill somebody the first time they touch it.
 
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