(a) All through-hull pipes required by this subpart must be made of steel or material equivalent to the hull in strength and fatigue resistance.
(b) All valves used as shell fittings and all shell fittings on which such valves are mounted must be made of steel, or bronze or other ductile material approved by the Commandant.
source: CGD 73-49R, 38 FR 12290, May 10, 1973, unless otherwise noted.
cite as: 46 CFR 45.153