§ 197.312 - Breathing supply hoses.
(a) Each breathing supply hose must -
(1) Have a maximum working pressure that is equal to or exceeds -
(i) The maximum working pressure of the section of the breathing supply system in which used; and
(ii) The pressure equivalent of the maximum depth of the dive relative to the supply source plus 100 psig;
(2) Have a bursting pressure of four times its maximum working pressure;
(3) Have connectors that -
(i) Are made of corrosion-resistant material;
(ii) Are resistant to accidental disengagement; and
(iii) Have a maximum working pressure that is at least equal to the maximum working pressure of the hose to which they are attached; and
(4) Resist kinking by -
(i) Being made of kink-resistant materials; or
(ii) Having exterior support.
(b) Each umbilical must -
(1) Meet the requirements of paragraph (a) of this section; and
(2) Be marked from the diver or open bell end in 10-foot intervals to 100 feet and in 50-foot intervals thereafter.