NEC Definition of Wet Location

NEC Article 100 defines a wet location as "a location where water is likely to drip, condense, or splash on equipment."

Concrete Slabs

The NEC does not specifically address whether concrete slabs, in general, are considered wet locations. However, it provides guidance for installations in specific circumstances:

Slabs in Contact with Earth

Slabs that are in direct contact with the earth are considered wet locations (NEC 334.3(A)).

Elevated Slabs

Slabs that are not in direct contact with the earth are not considered wet locations unless there is evidence that they are subject to excessive moisture (NEC 334.3(B)).

Your Interpretation

Your interpretation that any concrete slab is a wet location is not supported by the NEC. The NEC does not state that all concrete slabs are wet locations, only those that are in contact with the earth or subject to excessive moisture.

Cooling Equipment

The wet location rating of a concrete slab is relevant to the installation of electrical equipment, such as cooling units. Cooling units may need to be rated for wet locations if they are installed on a slab that is in contact with the earth or is subject to excessive moisture.

Conclusion:

Not all concrete slabs are considered wet locations according to the NEC. Only slabs that are in contact with the earth or subject to excessive moisture are considered wet locations. This interpretation is supported by the NEC definitions and guidelines. Flag for review