interior manholes??

[Mike01]

Is there any reason why a manhole cannot be installed on the interior of a building? We have a building expansion where the existing electrical manhole is currently outside the building footprint however with the new addition the manhole cover will now be in the basement floor slab. I could not find anything preventing this just wondering everyone?s opinions and thoughts it carries multiple medium voltage lines for campus distribution.

 

[electricguy61]

I'm not sure of your application, but I would think that flooding and methane gas might be good reasons for manholes to be outside.

 

[Mike01]

??

??

The existing manhole will be supplied with a sump pump to prevent flooding, where would the methane be from?

 

[kingpb]

Manholes are considered a confined space, in that regard there are obviously unhealthy gases that can accumulate. Also, where is the sump pump going to discharge too?

If a failure occurred in the MH, would you have proper access to it for equipment and what not to perform repairs? And is there any concern that a fire in the MH could provide and ignition source for the building.

I would check building code requirements, specifically for occupancy class, and life safety.

All in all, I would say, not a good idea, but can't say for sure why I fell that way.