CHAPTER 14 Surface Supplied Mixed Gas Diving Procedures
Change A 14-17
Check the status of any other divers.
Have the dive partner or standby diver ventilate the afflicted diver to remove
any accumulated carbon dioxide in the helmet and ensure the correct oxygen
If there is any reason to suspect gas contamination, shift to the standby helium
oxygen supply and ventilate both divers, ventilating the non-affected diver
When ventilation is complete, have the dive partner or standby diver ascertain
whether the diver is breathing. The presence or absence of breath sounds will
be audible over the intercom.
If the diver appears not to be breathing, the dive partner/standby diver should
attempt to reposition the diver's head to open the airway. Airway obstruction
will be the most common reason why an unconscious diver fails to breathe.
Check afflicted diver for signs of consciousness:
If the diver has regained consciousness, allow a short period for stabili-
zation and then abort the dive.
If the diver remains unresponsive but is breathing, have the dive partner
or standby diver move the afflicted diver to the stage. This action need
not be rushed.
If the diver appears not to be breathing, maintain an open airway while
moving the diver rapidly to the stage.
Once the diver is on the stage, observe again briefly for the return of
If consciousness returns, allow a period for stabilization, then begin
If consciousness does not return, bring the diver to the first decompres-
sion stop at a rate of 30 fsw/min (or to the surface if the diver is in a no-
At the first decompression stop:
If consciousness returns, decompress the diver on the standard decom-
pression schedule using surface decompression.
If the diver remains unconscious but is breathing, decompress on the
standard decompression schedule using surface decompression.
If the diver remains unconscious and breathing cannot be detected in
spite of repeated attempts to position the head and open the airway, an
extreme emergency exists. One must weigh the risk of catastrophic,