Mechanical ventilation of unberthed passenger spaces
(1) In every ship to which these regulations apply engaged in the eastern trade area, other than a ship engaged exclusively in the river trade area, every space allocated for the accommodation of unberthed passengers situated-
(a) below the uppermost between deck; or
(b) in a compartment in an upper between deck that is completely covered by a long superstructure,
shall be ventilated by a trunked mechanical ventilation or other air change system approved by the Director:
Provided that, where such an uppermost between deck space or long superstructure has large openings in the sides of the ship with no means fitted whatsoever of closing the openings, the unberthed passenger compartment in the between deck next below and adjacent to such openings may, subject to the approval of the Director, be regarded as an uppermost between deck and may be exempt from the requirement to be ventilated by a trunked mechanical ventilation or other air change system.
(2) The approval, on completion, of any system of mechanical ventilation shall be conditional upon the results of anemometer tests with which the Director is satisfied that the system is efficient.
(3) Arrangements shall be made to ensure a sufficient supply of air in the event of a breakdown in any part of a mechanical ventilation system-
(a) by interconnecting the air ducts from two or more fans;
(b) by providing additional independent means of mechanical ventilation; or
(c) by providing spare gear, properly packed for storage, for each size of electric motor employed to operate any trunked mechanical ventilation or other air change system on the following scale-
(i) for direct current motors-
1 field cod
1 set of bearings
1 brush holder
1 set of carbon brushes; and
(ii) for alternating current motors-
1 set of stator windings, complete with insulation pieces
1 set of bearings.
(4) A trunked mechanical ventilation system, required to be fitted to any space pursuant to this regulation, shall be capable of delivering, under normal sea-going conditions, for each passenger of the maximum number for which the space may measure, at least 830 cubic feet of fresh air per hour.
(5) In any space so fitted with mechanical ventilation-
(a) the vitiated air shall exhaust direct to the open air; and
(b) in the case of any such space situated abreast the machinery or boiler casings or immediately above the machinery spaces, the delivery of fresh air required to be provided pursuant to paragraph (4) shall be increased, in each such case, by 33 per centum.