(a) On vessels carrying passengers at night, the master or person in charge must ensure that a suitable number of watchmen are in the vicinity of the cabins or staterooms and on each deck, to guard against and give alarm in case of fire or other danger.

(b) On a fish processing vessel of more than 100 GRT, there must be a suitable number of watchmen trained in firefighting onboard when hot work is being done, to guard against and give alarm in case of a fire.

(c) For the watchmen described in paragraph (a) of this section, the owner or operator of an uninspected passenger vessel not more than 300 GRT may substitute the use of fire detectors, heat detectors, smoke detectors, and high-water alarms with audible- and visual-warning indicators, in addition to other required safety alarms, only when each of the following conditions are met:

(1) Fire detectors are located in each space containing machinery or fuel tanks per § 181.400(c) of this chapter.

(2) All grills, broilers, and deep-fat fryers are fitted with a grease extraction hood per § 181.425 of this chapter.

(3) Heat and/or smoke detectors are located in each galley, public accommodation space, enclosed passageway, berthing space, and all crew spaces.

(4) High-water alarms are located in each space with a through hull fitting below the deepest load waterline, a machinery space bilge, bilge well, shaft alley bilge, or other space subject to flooding from sea water piping within the space, and a space below the waterline with non-watertight closure such as a space with a non-watertight hatch on the main deck.

(5) Each alarm has an audible- and visual-alarm indicator located at the normal operating station and, if the normal operating position is not continually manned and not navigating underway, in an alternate location that must provide the crew, and may at all times provide the passengers, immediate warning of a hazardous condition.

(6) The vessel is underway for no more than 12 hours in any 24-hour period, and the master of the vessel has chosen to operate with less than a three-watch system in accordance with § 15.705 of this part.