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
(i)
Being made of kink-resistant materials; or
(ii)
Having exterior support.
(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.