{"data":{"id":"us/46-cfr-154.345","jurisdiction":"us","citation":"46 CFR 154.345","heading":"Air locks.","body":"(a) An air lock may be used for access from a gas-dangerous zone on the weather deck to a gas-safe space.\n(b) Each air lock must:\n(1) Consist of two steel doors, at least 1.5 m (4.9 ft.) but not more than 2.5 m (8.2 ft.) apart, each gasketed and tight when tested with a fire hose at not less 207 kPa gauge (30 psig);\n(2) Have self-closing doors with no latches or other devices for holding them open;\n(3) Have an audible and visual alarm on both sides which are actuated when both door securing devices are in other than the fully closed position at the same time;\n(4) Have mechanical ventilation in the space between the doors from a gas-safe area;\n(5) Have a pressure greater than that of the gas-dangerous area on the weather deck;\n(6) Have the rate of air change in the space between the doors of at least 8 changes per hour; and\n(7) Have the space between the doors monitored for cargo vapor leaks under § 154.1350.\n(c) In addition to the requirements of paragraphs (a) and (b) of this section, no gas-safe space on a liquefied flammable gas carrier may have an air lock unless the space:\n(1) Is mechanically ventilated to make the pressure in the space greater than that in the air lock; and\n(2) Has a means of automatically de-energizing all electrical equipment that is not explosion-proof in the space when the pressure in the space falls to or below the pressure in the air lock.","path":["Title 46—Shipping","CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY","SUBCHAPTER O—CERTAIN BULK DANGEROUS CARGOES","PART 154—SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES","Subpart C—Design, Construction and Equipment"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-46.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:22Z","sha256":"805dcd8f658b745a15942bf47ecdd6a56cc3e0f8c3625a379a438a710e81bfd9","source_id":"us-cfr","stale":true,"prev":"us/46-cfr-154.340","next":"us/46-cfr-154.350"},"notice":"GroundRules: Original legal text. Not legal advice."}