{"operation":"document","citation":"33 CFR 154.2108","title":"Vapor-moving devices.","source_type":"regulation","agency":"United States Coast Guard","status":"current","official":true,"published_on":null,"effective_on":"2026-08-18","summary":"(a) Paragraphs (b) and (e) of this section apply only to facilities collecting vapors of flammable, combustible, or non-high flash point liquid cargoes.\n\n(b) Each inlet and outlet to a vapor-moving device that handles vapor that has not been inerted, enriched, or diluted in accordance with 33 CFR 15","machine_formats":{"json":"https://regulus.evalyn.ai/document/33-cfr-154-2108.json","markdown":"https://regulus.evalyn.ai/document/33-cfr-154-2108.md"},"app_url":"https://regulus.evalyn.ai/document/33-cfr-154-2108","source_url":"https://www.ecfr.gov/on/2026-08-18/title-33/section-154.2108","body":"(a) Paragraphs (b) and (e) of this section apply only to facilities collecting vapors of flammable, combustible, or non-high flash point liquid cargoes.\n\n(b) Each inlet and outlet to a vapor-moving device that handles vapor that has not been inerted, enriched, or diluted in accordance with 33 CFR 154.2107 must be fitted with a detonation arrester; however, the outlet detonation arrester may be omitted if the vapor-moving device is within 50 times the pipe's diameter of the detonation arrester required by 33 CFR 154.2109(a).\n\n(c) If the vapor is handled by a reciprocating or screw-type compressor in the vapor collection system, the compressor must be installed with indicators and audible and visible alarms to warn against the following conditions:\n\n(1) Excessive gas temperature at the compressor outlet;\n\n(2) Excessive cooling water temperature;\n\n(3) Excessive vibration;\n\n(4) Low lube oil level;\n\n(5) Low lube oil pressure; and\n\n(6) Excessive shaft bearing temperature.\n\n(d) If the vapor is handled by a liquid ring-type compressor in the vapor collection system, it must be installed with indicators and audible and visible alarms to warn against the following conditions:\n\n(1) Low level of liquid sealing medium;\n\n(2) Lack of flow of the liquid sealing medium;\n\n(3) Excessive temperature of the liquid sealing medium;\n\n(4) Low lube oil level;\n\n(5) Low lube oil pressure, if pressurized lubricating system; and\n\n(6) Excessive shaft bearing temperature.\n\n(e) If the vapor is handled by a centrifugal compressor, fan, or lobe blower in the vapor collection system, construction of the blades or housing must be one of the following:\n\n(1) Blades or housing of nonmetallic construction;\n\n(2) Blades and housing of nonferrous material;\n\n(3) Blades and housing of corrosion resistant steel;\n\n(4) Ferrous blades and housing with one-half inch or more design tip clearance;\n\n(5) Nonferrous blades and ferrous housing with one-half inch or more design tip clearance; or\n\n(6) Blades of aluminum or magnesium alloy and a ferrous housing with a nonferrous insert sleeve at the periphery of the impeller.","truncated":false,"body_characters":2103}