Section 72.15-15 - Ventilation for closed spaces(a) 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) The ventilation of spaces which are "specially suitable for vehicles" shall be in accordance with the provisions of this paragraph. In addition, if vehicles are operated inside of enclosed spaces, the ventilation shall be in accordance with subpart 78.83 of this subchapter.(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 shall be such as to prevent air stratification as well as to prevent 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.CGFR 66-50, 30 FR 16903, Dec. 30, 1965, as amended by CGFR 66-33, 31 FR 15281, Dec. 6, 1966