46 C.F.R. § 111.05-21 Ground detection.
Title 46 - Shipping
There must be ground detection for each: (a) Electric propulsion system; (b) Ship's service power system; (c) Lighting system; and (d) Power or lighting distribution system that is isolated from the ship's service power and lighting system by transformers, motor generator sets, or other devices.
Title 46: Shipping
PART 111—ELECTRIC SYSTEMS—GENERAL REQUIREMENTS
Subpart 111.05—Equipment Ground, Ground Detection, and Grounded Systems
§ 111.05-21 Ground detection.
