Submersible compression chambers
334A diving supervisor shall ensure that no underwater diving operation is conducted from a lock-out submersible unless
(a)
the submersible is negatively buoyant on the bottom or positively secured to the underwater work area,
(b)
there is a stand-by diver monitoring the operation from the lock-out submersible, and
(c)
the diver’s umbilical is limited to 30 m.