Collapse to view only § 112.05-1 - Purpose; preemptive effect.

§ 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.

[CGD 74-125A, 47 FR 15267, Apr. 8, 1982, as amended by CGD 94-108, 61 FR 28286, June 4, 1996; 61 FR 36787, July 12, 1996; USCG-2006-24797, 77 FR 33882, June 7, 2012]

§ 112.05-3 - Main-emergency bus-tie.

Each bus-tie between a main switchboard and an emergency switchboard must:

(a) Disconnect automatically upon loss of potential at the emergency switchboard;

(b) Be arranged to prevent parallel operation of an emergency power source with any other source of electric power, except for interlock systems for momentary transfer of loads; and

(c) If arranged for feedback operation, open automatically upon overload of the emergency power source before the emergency power source is tripped off the line from the overload.

§ 112.05-5 - Emergency power source.

(a) The emergency power source must meet Table 1 to 112.05-5 and have the capacity to supply all loads, at a unity (1.0) service factor, that are simultaneously connected to it, except a load on a bus-tie to the main switchboard or non-required loads that are connected in accordance with § 112.05-1(c).

Table 1 to § 112.05-5(a)

Size of vessel and service Type of emergency power source or lighting Period of operation and minimum capacity of emergency power Passenger vessels: Ocean, Great Lakes, or coastwise; or on an international voyageTemporary emergency power source; and final emergency power source (automatically connected storage battery or an automatically started generator)36 hours. 1 2Other than Ocean, Great Lakes, or coastwise and not on an international voyageFinal emergency power source (automatically connected storage battery or an automatically started generator)8 hours or twice the time of run, whichever is less. 2Cargo vessels; miscellaneous self-propelled vessels; tankships; barges with sleeping accommodations for more than 6 persons; mobile offshore drilling units; and oceanographic vessels: Ocean, Great Lakes, or coastwise and 500 GT or more; on an international voyage and 500 GT or more; or all waters and 1600 GT or moreFinal emergency power source (automatically connected storage battery or an automatically started generator)18 hours. 1 2Ocean, Great Lakes, or coastwise and less than 500 GT; or other than ocean, Great Lakes, or coastwise, 300 GT or more but less than 1600 GT, and not on an international voyage.Emergency lighting provided by an automatically connected or manually controlled storage battery; automatically or manually started generator; or relay-controlled, battery-operated lanterns. 3 46 hours or twice the time of run, whichever is less.

1 A 12-hour power supply may be especially considered for vessels engaged regularly in voyages of short duration.

2 The capacity for the operation of the steering gear, as required by § 58.25-65, is for a period of 30 minutes continuous operation.

3 The emergency lighting requirements of § 112.15-1 (b), (c), (f), and (g) must be met.

4 Requirements of Subpart 112.39 must be met by the relay-controlled, battery-operated lanterns.

(b) The emergency power source must be independent of the ship's service lighting and powerplant and propulsion plant, except for the compressed air starting means allowed in § 112.50-7(c)(3)(i). A stop control for an emergency generator must be only in the space that has the emergency generator, except a remote mechanical reach rod is permitted for the fuel oil shut-off valve to an independent fuel oil tank located in the space.

(c) The complete emergency installation must function at full rated power when the vessel is upright or inclined to the maximum angle of heel that results from the assumed damage defined in 33 CFR part 155 or in subchapter S of this chapter for the specific vessel type or 22.5 degrees, whichever is greater; when the trim of the ship is 10 degrees, either in the fore or aft direction, or is in any combination of angles within those limits.

(d) The emergency power source, its associated transforming equipment, and the emergency switchboard must be located aft of the collision bulkhead, outside of the machinery casing, and above the uppermost continuous deck. Each compartment containing this equipment must be readily accessible from the open deck and must not contain machinery not associated with, or equipment not in support of, the normal operation of the emergency power source. Equipment in support of the normal operation of the emergency power source includes, but is not limited to, ventilation fans, CO2 bottles, space heaters, and internal communication devices, such as sound powered phones.

(e) No compartment that has an emergency power source or its vital components may adjoin a Category A machinery space or those spaces containing the main source of electrical power and its vital components.

(f) Except for a cable for connecting equipment in the engineroom or boilerroom, no cable supplied from the emergency switchboard may penetrate the boundaries of the engineroom, boilerroom, uptakes, or casings of these spaces. These cables must be kept clear of the bulkheads and decks forming these boundaries. No emergency circuit in an engineroom or a boilerroom may supply equipment in any other space.

(g) The emergency switchboard must be as near as practicable to the emergency power source but not in the same space as a battery emergency power source.

(h) If the emergency power source is a generator, the emergency switchboard must be in the same space as the emergency power source.

(i) The prime mover of an emergency generator must be either a diesel engine or a gas turbine.

[CGD 74-125A, 47 FR 15267, Apr. 8, 1982, as amended by CGD 94-108, 61 FR 28286, June 4, 1996; 62 FR 23910, May 1, 1997; USCG-2020-0075, 88 FR 16368, Mar. 16, 2023]

§ 112.05-7 - Use of emergency generator in port.

The emergency generator may be used during lay time in port for supplying power to the vessels, provided the following:

(a) The fuel oil tank for the emergency generator prime mover must be appropriately sized and provided with a level alarm, which is to be set to alarm at a level where there is sufficient fuel oil capacity for the emergency services for the period of time required by § 112.05-5(a).

(b) The emergency generator prime mover is to be rated for continuous service.

(c) The prime mover is to be fitted with alarms, displays and automatic shutdown arrangements that meet ABS Marine Vessel Rules (incorporated by reference, see § 110.10-1 of this subchapter), section 4-8-2/5.19 Table 2, except that for fuel oil tank low-level alarm, in paragraph (a) of this section is to apply instead. The displays and alarms are to be provided in the centralized control station. Monitoring at the engineers' quarters must meet ABS Marine Vessel Rules, section 4-9-6/19.

(d) The emergency generator room is to be fitted with fire detectors. Where the emergency generator is located in a space separated from the emergency switchboard, fire detectors are to be located in each space. The fire detection and alarm system must meet the requirements of subpart 113.10 of this subchapter.

(e) The power supply circuits, including control and monitoring circuits, for the use of an emergency generator in port are to be so arranged and protected that any electrical fault, except for the emergency generator and the emergency switchboard, will not affect the operation of the main and emergency services.

(f) Means are to be provided to readily change over to emergency operation.

(g) The generator is to be safeguarded against overload by automatically shedding such other loads so that the supply to the required emergency loads is always available.

(h) Operational instructions such as that on the fuel oil tank level, harbor/seagoing mode changeover arrangements, etc. are to be provided on board. Before the vessel is under way, all valves, switches, etc., are to be in the positions for the intended mode of operation of the emergency generator and the emergency switchboard. Such instructions are to be distinctly posted at the emergency generator room. Planned maintenance is to be carried out only while in port.

[USCG-2020-0075, 88 FR 16368, Mar. 16, 2023]