When a conduit containing service entrance conductors runs beneath a building, what is the minimum depth of concrete required to cover a conduit for it to be considered 'outside' the building?

When a conduit containing service entrance conductors runs beneath a building, what is the minimum depth of concrete required to cover a conduit for it to be considered 'outside' the building?

• A. 2 in.
• B. 6 in.
• C. 12 in.
• D. 18 in.

Answer: (A)

When a conduit carrying service entrance conductors runs beneath a building, the amount of concrete above it determines how it's treated for protection purposes. Concrete over the conduit provides mechanical protection, and a small but sufficient cover is considered enough to classify the run as effectively outside the building. Two inches of concrete is the minimum required to count as outside protection, balancing adequate protection with practical installation under slabs. Deeper covers like six, twelve, or eighteen inches are more about increasing protection in harsher scenarios or direct burial depths, but they aren’t needed to meet the “outside” classification for this particular situation.

When a conduit carrying service entrance conductors runs beneath a building, the amount of concrete above it determines how it's treated for protection purposes. Concrete over the conduit provides mechanical protection, and a small but sufficient cover is considered enough to classify the run as effectively outside the building. Two inches of concrete is the minimum required to count as outside protection, balancing adequate protection with practical installation under slabs.

Deeper covers like six, twelve, or eighteen inches are more about increasing protection in harsher scenarios or direct burial depths, but they aren’t needed to meet the “outside” classification for this particular situation.