21-26 Change A
U.S. Navy Diving Manual—Volume 5
21-5.6.8.1.2 Table 5. On Table 5, oxygen should be breathed by the tender during the final 30-
minute ascent to the surface. If the tender has had a previous hyperbaric exposure,
an additional 20 minutes of oxygen breathing is required at 30 feet prior to ascent.
(See Table 21-6.)
21-5.6.8.1.3 Table 6. For an unmodified Table 6 or when there has been only a single exten-
sion at 60 or 30 feet, the tender breathes 100 percent oxygen for the final 30
minutes at 30 feet and during ascent to the surface. If there has been more than one
extension, oxygen breathing is done for the last 60-minute period at 30 feet and
during ascent to the surface. If the tender has had a dive/hyperbaric exposure
within the past 12 hours, an additional 60-minute oxygen breathing period at 30
feet is required. (See Table 21-6.)
21-5.6.8.1.4 Table 6A. For an unmodified Table 6A or when there has been only a single
extension at 60 or 30 feet, the tender breathes 100 percent oxygen for the final 60
minutes at 30 feet and during ascent to the surface. If there has been more than one
extension, oxygen breathing is done for 90 minutes at 30 feet and during ascent to
the surface. If the tender has had a dive/hyperbaric exposure within the past 12
hours, an additional 60-minutes of oxygen at 30 feet is required. (See Table 21-6.)
21-5.6.8.1.5 Table 9. On Table 9, the tender breathes 100 percent oxygen during the last 15
minutes at 45 feet and during ascent to the surface, regardless of the ascent rate
used.
21-5.6.8.1.6 Tending Frequency. Normally, tenders should allow a surface interval of at least
12 hours between consecutive treatments on Tables 1A, 2A, 3, 5, 6, and 6A, and at
least 48 hours between consecutive treatments on Tables 4, 7, and 8. If necessary,
however, tenders may repeat Treatment Tables 5, 6, or 6A within this 12-hour
surface interval if oxygen is breathed at 30 feet and shallower as outlined above.
Minimum surface intervals for Tables 1A, 2A, 3, 4, and 7 shall be strictly
observed.
21-5.7
Loss of Oxygen During Treatment. Loss of oxygen breathing capability during
oxygen treatments is a rare occurrence. However, should this occur, the following
should be done:
If repair can be effected within 15 minutes:
Maintain depth until repair is completed.
After O
2
is restored, resume treatment at point of interruption.
If repair can be effected after 15 minutes but before 2 hours:
Maintain depth until repair is completed.
After O
2
is restored: If original table was Table 5, 6, or 6A, complete treatment
with maximum number of O2 extensions.
21-5.7.1
Compensation. If Table 4, 7, or 8 is being used, no compensation in decompres-
sion is needed if O2 lost. If decompression must be stopped because of worsening
