46 C.F.R. § 153.368 Pressure-vacuum valves.
Title 46 - Shipping
(a) The pressure side of a required pressure-vacuum relief valve must begin to open only at a pressure exceeding 3.5 kPa gauge (approx. 0.5 psig). (b) A pressure-vacuum relief valve must meet the requirements of Subpart 162.017 of this chapter.
Title 46: Shipping
PART 153—SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS
Subpart B—Design and Equipment
Cargo Venting Systems
§ 153.368 Pressure-vacuum valves.
