A compressor used to supply breathing air to a diver must have—
(a)
A volume tank that is—
(1)
Built and stamped in accordance with section VIII, division 1 of the ASME Code with—
(i)
A check valve on the inlet side;
(iii)
A relief valve; and
(2)
Tested after every repair, modification, or alteration to the pressure boundaries as required by § 197.462 ;
(b)
Intakes that are located away from areas containing exhaust fumes of internal combustion engines or other hazardous contaminants;
(c)
An efficient filtration system; and
(d)
Slow-opening shut-off valves when the maximum allowable working pressure of the system exceeds 500 psig.