An employer must ensure that a recompression chamber is available for immediate use whenever diving operations take place, at a depth exceeding-
(a) fifty metres;
(b) ten metres, but not exceeding fifty metres where the routine decompression time exceeds twenty minutes;
or
(c) ten metres, but not exceeding fifty metres where the routine decompression time is twenty minutes or less
and effective arrangements have not been made for a diver requiring therapeutic recompression to be brought to a suitable chamber within two hours from the time when the need for recompression is identified.