Figure 14-3. He02 Diving Chart.
14-3.8 Emergency SUR D Procedures Using Oxygen. A diver is eligible for emergency surface decompression if he is on oxygen at the 40-fsw water stop and is within 5 minutes of repeating the 50-fsw stop time. If there is no 50-fsw stop, 5 minutes on oxygen at 40 fsw is required.
Example. If the 50-fsw stop time is 12 minutes, the diver must remain at 40 fsw breathing oxygen for 7 minutes before emergency surface decompression can be initiated.
The emergency surface decompression procedure is identical to the normal surface decompression procedure except that the length of the first oxygen breathing period at 40 fsw in the recompression chamber is lengthened from 30 minutes to 40 minutes. An emergency surface decompression dive chart is shown Figure 14-5; the profile is shown in Figure 14-6.
14-3.9 Aborted Dive During Descent. Follow these procedures when a dive must be aborted during descent.
14-3.9.1 Dive Aborted at 200 fsw or Shallower.
■ Add any time spent shifting gases at 20 fsw to the bottom time to derive a corrected bottom time.
Enter the table at the deepest depth attained by the diver and select the schedule corresponding to the corrected bottom time.
Decompress according to the indicated schedule.
14-3.9.2 Dive Aborted Deeper than 200 fsw.
■ No correction of the bottom time for time spent at 20 fsw is needed.
Enter the table at the deepest depth attained by the diver and select the schedule corresponding to the bottom time.
14-3.9.3 No-Decompression Limits. In many instances the diver will be observed to fall within the no-decompression limits when the above procedures are followed.
If the diver falls within the no-decompression limits and is breathing at least 16 percent oxygen, surface the diver at 30 fsw/minute.
If the diver falls within the no-decompression limits but is breathing less than 16 percent oxygen:
1. Bring the diver to 20 fsw at 30 fsw/minute.
2. Shift the diver to air and ventilate.
Bottom Mix: 15%
Rig: M K-21
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