Annual Diving Report - Divers Alert Network

5. BREATH-HOLD DIVING
5.4 Breath-Hold Diving Wisely
Breath-hold divers must be respectful of their limits. Voluntary breath-hold can be a simple effort,
but also a dangerous one. The one fatal swimming pool incident in this sample stands as a good
example. The victim was a 33-year-old male diving instructor practicing with no supervision. The
specific factors leading up to his death cannot be determined, but the lack of apparent injury
suggested that an unexpected loss of consciousness was involved. Pool breath-hold is often
conducted as a challenge or training activity, with the primary focus on improving breath-hold time
during resting (static) or swimming (dynamic) breath-hold. A variety of techniques, including
relaxation and voluntary hyperventilation, may be practiced to increase performance. Pools can
provide a relatively controlled setting to try new techniques and test personnel limits. The
apparently benign nature of the environment, however, quickly turns if adequate safeguards are
not in place. The most important practices to protect freedivers are direct supervision and access.
Access is not usually a problem given the shallow water and good visibility. The absence of direct
supervision was the critical problem in this case. Unconsciousness can result from seemingly
modest efforts to prolong breath-hold time in many circumstances. The lack of warning that can
precede unconsciousness is not something that can be 'overcome' by motivation or certifications.
This is a prime example of how complacency can kill. Adequate safeguards are always required
to ensure safety. The risks are dramatically reduced by close monitoring of a partner throughout
his or her pre-breath-hold workup, the breath-hold and the first 30 seconds post- breath-hold (the
risk continues post-breath-hold since it takes time for the oxygen in an inspired breath to reach
the brain). A simple two-person, one-up-one-down buddy team with committed direct supervision
will be sufficient to manage most potentially serious problems in a pool. While additional
safeguards are required to ensure the same monitoring capability in more complex environments
or breath-hold diving operations, the core concept is simple. Direct supervision during the prebreath-hold,
breath-hold, and post-breath-hold saves lives.
The case reports found in Appendix C provide additional opportunity to reflect upon how easy it
can be to run into problems. They can be useful to think about when reviewing individual
practices and procedures.
5.5 Summary
A dedicated program is in place to collect data on breath-hold diving incidents. The current report
is predominantly comprised of fatal incidents. Documentation of non-fatal incidents remains
elusive. Data from both fatal and non-fatal cases would provide valuable information to improve
awareness, facilitate training and promote procedural evaluations. Further effort will be directed at
expanding case reporting.
Annual Diving Report: 2006 Edition 63