Section 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-OES);(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-OES);(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-OES); 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; USCG-2014-0688, 79 FR 58285, Sept. 29, 2014