CFR > Title 46 - Shipping > CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY > SUBCHAPTER I—CARGO AND MISCELLANEOUS VESSELS (parts 90 to 105) > PART 105—COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS > SUBPART 105.20—Specific Requirements—Cargo Tanks (§105.20-1 to §105.20-15) > 105.20-5—Piping systems.

105.20-5—Piping systems.

(a) Piping shall be copper, nickel copper, or copper nickel having a minimum wall thickness of 0.035″; except that seamless steel pipe or tubing which provides equivalent safety may be used for diesel cargo systems.
(b) Valves shall be of a suitable nonferrous metallic Union Bonnet type with ground seats except that steel or nodular iron may be used in cargo systems utilizing steel pipe or tubing.
(c) Aluminium or aluminum alloy valves and fittings are prohibited for use in cargo lines.