46 CFR § 112.05-1 - Purpose; preemptive effect.
(a) The purpose of this part is to ensure a dependable, independent, and dedicated emergency power source with sufficient capacity to supply those services that are necessary for the safety of the passengers, crew, and other persons in an emergency and those additional loads that may be authorized under paragraph (c) of this section.
(b) No load may be powered from an emergency power source, except:
(1) A load required by this part to be powered from the emergency power source;
(2) A bus-tie to the main switchboard that meets § 112.05-3; and
(3) Emergency loads that may be necessary to maintain or restore the propulsion plant, such as control systems, controllable pitch propellers, hydraulic pumps, control air compressors, and machinery necessary for dead-ship start-up.
(c) Other loads may be authorized by the Commanding Officer, Marine Safety Center (MSC), to be connected to the emergency source of power to provide an increased level of safety in recognition of a unique vessel mission or configuration. When these loads are authorized, the emergency power source must—
(1) Be sized to supply these loads using a unity (1.0) service factor; or
(2) Be provided with automatic load shedding that removes these loads and operates before the emergency generator trips due to overload. The automatic load shedding circuit breakers must be manually reset.
(d) The regulations in this part have preemptive effect over State or local regulations in the same field.