Every self-contained breathing apparagraphtus shall :-
(a) be of the open circuit compressed air type and shall be of a approved type;
(b) be capable of functioning for at least 30 minutes and shall be provided with not more than one face mask unless the apparagraphtus has been approved for use with a second face mask which may be used in emergency;
(c) contain storage capacity of the compressed air cylinder or cylinders attached to the apparagraphtus and carried by the weather of at least 1,200 litres of free air. The storage cylinders shall be of sufficient strength and be capable of withstanding hydraulic pressure in excess of the maximum working pressure.
(d) contain provision for automatic regulation of air supply to the wearer of the apparagraphtus in accordance with his breathing requirements when he is breathing any volume of free air of up to 85 litres per minute at any time when the pressure in the supply cylinder or cylinders is above 10.5 bars (1.05 N/mm2). Means shall be provided for overriding the automatic air supply to increase the volume of air available to the wearer if required.
(f) not weigh more than 16 kilo grammes excluding any lifeline and if they do not foam an integral part of the apparagraphtus, any safety belt or harness;
(g) be provided with fully charged spare cylinders having a spare storage capacity of at least 2,400 litres of free air except where :
(i) the ship is carrying five sets or more of such apparagraphtus the total spare storage capacity of free air shall not be required to exceed 9,600 litres; or
(ii) the ship is equipped with means for recharging the air cylinders to full pressure with air, free from contamination, the spare storage capacity of the fully charged spare cylinders of each such apparagraphtus shall be of at least 1,200 litres of free air and the total spare storage capacity of free air provided in the ship shall not be required to exceed 4,800 litres.
(h) contain provision for warning the wearer audibly when 80 per cent of usable capacity of the apparagraphtus has been consumed.
(i) accompany a servicing and instruction manual.