CFR > Title 46 - Shipping > CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY > SUBCHAPTER O—CERTAIN BULK DANGEROUS CARGOES (parts 150 to 155) > PART 154—SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES > SUBPART D—Special Design and Operating Requirements (§154.1700 to §154.1760) > 154.1725—Ethylene oxide.

154.1725—Ethylene oxide.

(a) A vessel carrying ethylene oxide must:
(1) Have cargo piping, vent piping, and refrigeration equipment that have no connections to other systems;
(2) Have valves, flanges, fittings, and accessory equipment made of steel, stainless steel, except types 416 and 442, or other material specially approved by the Commandant (CG-522);
(3) Have valve disk faces, and other wearing parts of valves made of stainless steel containing not less than 11% chromium;
(4) Have gaskets constructed of spirally wound stainless steel with teflon or other material specially approved by the Commandant (CG-522);
(5) Not have asbestos, rubber, or cast iron components in the cargo containment system and piping;
(6) Not have threaded joints in cargo piping;
(7) Have a water spray system under § 154.1105 that protects the above deck cargo piping; and
(8) Have a nitrogen inerting system or on board nitrogen gas storage that can inert the vapor space of an ethylene oxide cargo tank for a period of 30 days under the condition of paragraph (e) of this section.
(b) Cargo hose used for ethylene oxide must:
(1) Be specially approved by the Commandant (CG-522); and
(2) Be marked “For (Alkylene or Ethylene) Oxide Transfer Only.”
(c) Ethylene oxide must be maintained at less than 30 °C (86 °F).
(d) Cargo tank relief valves for tanks containing ethylene oxide must be set at 539 kPa gauge (78.2 psig) or higher.
(e) The vapor space of a cargo tank carrying ethylene oxide must be maintained at a nitrogen concentration of 45% by volume.
(f) A vessel must have a method for jettisoning ethylene oxide that meets §§ 154.356 and 154.1872.
[CGD 74-289, 44 FR 26009, May 3, 1979, as amended by CGD 82-063b, 48 FR 4782, Feb. 3, 1983]