U.S. Code of Federal Regulations
Regulations most recently checked for updates: Oct 26, 2020
(a) Each indicator must be independent of the propulsion control system. A failure of the propulsion control system must not affect the operation of the indicators.
(b) Each electric component or its enclosure must meet Type 4 or 4X of NEMA 250 or IP 56 of IEC 60529 (both incorporated by reference; see 46 CFR 110.10-1) requirements.