THE HONG KONG GOVERNMENT GAZETTE, JANUARY 31, 1941.
Where the sides of stairways are not bounded by bulkheads etc., an additional rail is to be fitted under each handrail.
(9) At least six feet clear headroom is to be provided above each stair tread.
(10) Stairways should be arranged in a fore and aft direction and the angle from the vertical should be as near 37 degrees as possible.
(11) The Principal Surveyor of Ships will be prepared to consider departures in detail from the foregoing instruc- tions to meet exceptional circumstances provided that ample ineans of exit are furnished from each compartment in case of emergency.
(12) Proper arrangements are to be made for access to spaces above the weather deck which are intended for the use of unberthed passengers.
12. VENTILATION.-(1) General. (a) The ventilation of unberthed passenger compartments should, as far as practicable, be arranged to ensure the maximum distribution of fresh air throughout the accommodation. All such compartments which are situated below the uppermost between deck are to be properly ventilated by mechanical means. Provided that in cases where an uppermost between deck space has large openings in the ship's sides with no means of closing, the unberthed passenger compartments in the between deck next below, may, subject to the approval of the Principal Surveyor of Ships, be regarded as uppermost between deck spaces for the purpose of this paragraph.
The surveyor is to recommend that upper between deck compartments which are completely covered by long superstructures should be ventilated by mechanical means.
(b) As far as may be possible the ventilation of each passenger compartment is to be separate and distinct from that of all other compartments. It is not permissible for the means provided for the ventilation of any passenger compart- ment, whether natural or mechanical, to be common with those adopted for the ventilation of any space not used exclusively for the accommodation of passengers or crew.
(c) Shafts constructed solely for ventilation may be accepted as air outlets when serving compartments ventilated naturally or mechanically, provided that their coamings extend sufliciently high above the weather deck to permit these ven- tilators to remain open in ordinary weather.
Where a ventilation shaft is used in combination with natural ventilation its area must be at least double that of a cowl ventilator doing similar duty.
(d) No ventilator is to be carried through any watertight bulkhead without the consent of the Principal Surveyor of Ships.
(e) When the surveyor considers it necessary, suitable protection to guard against the risk of fire is to be provided.
(f) Plans showing the proposed ventilation arrangements are to be submitted for the consideration of the Principal Surveyor of Ships, but it should be noted that acceptance of any system of mechanical ventilation will be conditional upon satisfactory anemometer tests on board the ship.
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