{"data":{"id":"us/46-cfr-197.434","jurisdiction":"us","citation":"46 CFR 197.434","heading":"Surface-supplied mixed-gas diving.","body":"The diving supervisor shall insure that—\n(a) When mixed-gas diving is conducted, a decompression chamber or a closed bell meeting the requirements of § 197.332 is ready for use at the dive location;\n(b) A diving stage is used except when a bell is provided;\n(c) A bell is used for dives deeper than 220 fsw or when the dive involves in-water decompression times greater than 120 minutes, except when the diver is using a heavy-weight diving outfit or is diving in a physically confining space;\n(d) A closed bell is used for dives at depths greater than 300 fsw, except when diving is conducted in a physically confining space;\n(e) A separate dive team member tends each diver in the water;\n(f) A standby diver is available during all nonsaturation dives;\n(g) When saturation diving is conducted—\n(1) A standby diver is available when the closed bell leaves the dive location until the divers are in saturation; and\n(2) A member of the dive team at the dive location is a diver able to assist in the recovery of the closed bell or its occupants, if required;\n(h) When closed bell operations are conducted, a diver is available in the closed bell to assist a diver in the water;\n(i) When a diver is in a physically confining space, another diver is stationed at the underwater point of entry and is line-tending the diver;\n(j) Each diving operation has a primary and secondary breathing gas supply meeting the requirements of § 197.340; and\n(k) The surface-supplied mixed-gas diver has the equipment required by § 197.346 (b) or (d).","path":["Title 46—Shipping","CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY","SUBCHAPTER V—MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS","PART 197—GENERAL PROVISIONS","Subpart B—Commercial Diving Operations"],"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":"c685c5ca8b996f63ae7175db2343de5899bd3a5307a39d3ac806956fcfcef0ca","source_id":"us-cfr","stale":true,"prev":"us/46-cfr-197.432","next":"us/46-cfr-197.436"},"notice":"GroundRules: Original legal text. Not legal advice."}