What is a key requirement for luminaires installed in wet locations?

Luminaires installed in wet locations must be listed for wet locations to ensure safety and functionality. This listing signifies that the luminaire is tested and approved for use in environments where it is exposed to moisture and rain. Such luminaires are designed with materials and construction techniques that provide protection against water ingress, which is critical to prevent electrical failures or hazards like short circuits or electrical shocks.

While double insulation, having a cover, and being hardwired can all contribute to safety in certain contexts, they do not specifically address the unique requirements of wet location installations. The listing for wet locations is a comprehensive requirement that encompasses various safety aspects, ensuring that all components of the luminaire can withstand the conditions present in such environments. Thus, the specific designation of being "listed for wet locations" is vital in adhering to the National Electrical Code and ensuring compliance with safety standards.