DIRECTIVE NUMBER: CPL 02-00-151 EFFECTIVE DATE ... - OSHA

from the dive team (indicating a possible disability of the diver or an equipment
failure); communications with the diver are lost and cannot quickly be
reestablished (either between the diver and the dive location or diving bell, or
between the diver and the designated person-in-charge and the skipper of the
support vessel for liveboating operations); or the diver begins to use the reserve
breathing gas. Any of these situations requires termination of the dive. The
decompression interval should not be omitted after termination of the dive if
doing so would add to the diver’s overall physical risk, unless the circumstances
make inwater decompression impossible or present a greater physical risk to the
diver.
G. 29 CFR 1910.423 Post-dive procedures.
1. 29 CFR 1910.423(b) Precautions. At the completion of a dive, the employer
must: thoroughly check the physical condition of the diver; instruct the diver to
report any physical problems or adverse physiological reactions (including
decompression sickness symptoms); advise the diver of the location of the
nearest decompression chamber; and alert the diver to the hazards of flying too
soon after the dive. As a general rule, a diver should wait 12 hours before
flying for air diving not involving decompression, and wait 24 hours for air
dives involving decompression and all mixed-gas diving. For additional
information, see the U.S. Navy Diving Manual or the NOAA Diving Manual.
Decompression sickness effects can occur for some time after the completion of
the dive, and sleep can conceal the onset of decompression sickness.
Consequently, after a dive deeper than 100 fsw, a dive that requires
decompression, or after any dive using a mixed-gas breathing mixture, the
employer is required to instruct the diver to remain awake and in the vicinity of
the decompression chamber at the dive location for at least one hour after the
dive, including one hour after any decompression or diving medical treatment
(such as medical treatment for decompression sickness or arterial gas
embolism).
2. 29 CFR 1910.423(c) Recompression capability. Decompression chambers
provide the only effective therapy (i.e., recompression) for decompression
sickness and arterial gas embolism. A decompression chamber also can reduce
a diver’s underwater exposure since chambers may be used to decompress the
diver on the surface (i.e., procedures known as “surface decompression on air”
and “surface decompression on oxygen”).
a. 29 CFR 1910.423(c)(1). This provision requires the use of a decompression
chamber capable of recompressing the diver at the surface to a minimum of
165 fsw (6 ATA) at the dive location for: SCUBA dives deeper than 100
fsw; surface-supplied air dives deeper than 100 fsw but shallower than 220
fsw; mixed-gas dives shallower than 300 fsw; or diving outside the nodecompression
limits shallower than 300 fsw.
b. 29 CFR 1910.423(c)(2). A decompression chamber capable of
recompressing the diver at the surface to the maximum depth of the dive
must be available at the dive location for dives deeper than 300 fsw.
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