197.328—PVHO—General.
(a)
Each PVHO, contracted for or purchased after February 1, 1979, must be built and stamped in accordance with ASME PVHO-1.
(b)
Each PVHO, contracted for or constructed before February 1, 1979, and not Coast Guard approved, must be submitted to the Coast Guard for approval prior to February 1, 1984.
(ii)
Pass the radiographic and other survey tests of welded joints required by section VIII, division 1 or division 2, as appropriate, of the ASME Code; and
(B)
The pneumatic test described in § 54.10-15 of this chapter and such additional tests as the Officer-in-Charge, Marine Inspection (OCMI) may require.
(1)
Have a shut-off valve located within 1 foot of the pressure boundary on all piping penetrating the pressure boundary;
(2)
Have a check valve located within 1 foot of the pressure boundary on all piping exclusively carrying fluids into the PVHO;
(4)
Have a built-in breathing system with at least one mask per occupant stored inside each separately pressurized compartment;
(5)
Have a two-way voice communications system allowing communications between an occupant in one pressurized compartment of the PVHO and—
(6)
If designed to mechanically couple to another PVHO, have a two-way communications system allowing communications between occupants of each PVHO when mechanically coupled;
(9)
Have viewports that meet the requirements of ASME PVHO-1 except those PVHO's approved under paragraph (b) of this section which have nonacrylic viewports;
(14)
Have a means of maintaining the oxygen content of the interior atmosphere below 25 percent surface equivalent by volume when pressurized with air as the breathing mixture;
(15)
Have a means of maintaining the interior atmosphere below 2 percent surface equivalent carbon dioxide by volume;
(16)
Have a means of overriding and controlling from the exterior all interior breathing and pressure supply controls;
(18)
Have interior electrical systems that are designed for the environment in which they will operate to minimize the risk of fire, electrical shock to personnel, and galvanic action of the PVHO; and
(19)
Be tested after every repair, modification, or alteration to the pressure boundaries as required by § 197.462.