46 CFR § 92.15-10 - Ventilation for closed spaces.
(a) Except as noted in paragraph (c) of this section, all enclosed spaces within the vessel shall be properly vented or ventilated. Means shall be provided to close off all vents and ventilators.
(b) Means shall be provided for stopping all fans in ventilation systems serving machinery and cargo spaces and for closing all doorways, ventilators and annular spaces around funnels and other openings to such spaces, from outside these spaces, in case of fire.
(c) On unmanned cargo barges not fitted with a fixed bilge system, vents and ventilators may be omitted from void spaces.
(d) The ventilation of spaces that are “specially suitable for vehicles” shall be in accordance with §§ 97.80–1, 111.105–39 and 111.105–40 of this chapter, as applicable.
(1) Areas below the weather deck shall be provided with continuous pressure-positive ventilation at each level on which vehicles are transported.
(2) The quantity of ventilating air shall be not less than 1 cubic foot per minute per square foot of deck area.
(3) The ventilation system shall be such as to prevent air stratification as well as to prevent the accumulation of air pockets.
(4) An alarm system shall be provided which will indicate the loss of required ventilation. The alarm location shall be in a normally manned space acceptable to the Commandant.
(e) For requirements regarding controls of electrically powered ventilation systems, see subchapter J (Electrical Engineering) of this chapter.