What is the permitted cover depth in inches for pool, spa, and fountain lighting installed in a nonmetallic raceway under certain conditions?

The correct answer regarding the permitted cover depth for pool, spa, and fountain lighting installed in a nonmetallic raceway is 6 inches. This specification aligns with electrical codes that aim to ensure safety around bodies of water. The shallow cover depth is sufficient because the nonmetallic raceway provides a degree of protection for the conductors, allowing for safe installation while minimizing the risk of accidental damage.

In certain environments, like areas around swimming pools or spas, factors such as accessibility and the potential for water exposure must be carefully considered. A cover depth of 6 inches allows for both grounding and protective measures to be established without requiring excessive excavation or installation effort, which could complicate maintenance or create hazards if deeper trenches were mandated.

Other options represent cover depths that are not necessary or appropriate for this particular application, as deeper cover could lead to unnecessary effort and complications without significant benefits to safety or functionality in the context of nonmetallic raceways specifically designed for pool and spa lighting installations.