33 CFR § 183.520
Fuel tank vent systems
August 2, 2023
§ 183.520 Fuel tank vent systems.
(a) Each fuel tank must have a vent system that prevents pressure in the tank from exceeding 80 percent of the pressure marked on the tank label under § 183.514(b)(5).
(b) Each vent must:
(1) Have a flame arrester that can be cleaned unless the vent is itself a flame arrestor; and
(2) Not allow a fuel overflow at the rate of up to two gallons per minute to enter the boat.
[CGD 74–209, 42 FR 5950, Jan. 31, 1977, as amended by CGD 77–98, 42 FR 36253, July 14, 1977]