46 C.F.R. § 197.434 Surface-supplied mixed-gas diving.
Title 46 - Shipping
The diving supervisor shall insure that— (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; (b) A diving stage is used except when a bell is provided; (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; (d) A closed bell is used for dives at depths greater than 300 fsw, except when diving is conducted in a physically confining space; (e) A separate dive team member tends each diver in the water; (f) A standby diver is available during all nonsaturation dives; (g) When saturation diving is conducted— (1) A standby diver is available when the closed bell leaves the dive location until the divers are in saturation; and (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; (h) When closed bell operations are conducted, a diver is available in the closed bell to assist a diver in the water; (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; (j) Each diving operation has a primary and secondary breathing gas supply meeting the requirements of §197.340; and (k) The surface-supplied mixed-gas diver has the equipment required by §197.346 (b) or (d).
Title 46: Shipping
PART 197—GENERAL PROVISIONS
Subpart B—Commercial Diving Operations
specific diving mode procedures
§ 197.434 Surface-supplied mixed-gas diving.
