What requirement must be met for a luminaire marked "Suitable for Wet Locations" when used in damp locations?

A luminaire marked "Suitable for Wet Locations" is specifically designed to withstand moisture, rain, or water exposure, making it inherently suitable for severe conditions. When such a luminaire is used in damp locations, it continues to meet safety and operational standards as outlined in the National Electrical Code (NEC). The code recognizes that a luminaire rated for wet locations can be utilized in less severe environments, like damp locations, without compromising safety.

The designation for wet locations indicates robust construction, which likely offers better protection against moisture than needed in a damp environment. By allowing luminaires deemed suitable for wet locations to be used in damp areas, the NEC ensures flexibility in design while maintaining safety standards. This approach encourages the use of higher-rated luminaires in less demanding conditions, promoting reliable lighting solutions.

In contrast, other choices like not using the luminaire, ensuring proper installation, or avoiding it altogether are not applicable here because they do not align with the intent and flexibility provided by NEC guidelines. Thus, permitting the use of wet-rated luminaires in damp locations is both a practical and compliant option within the electrical code.