This is an old revision of this page, as edited by Mark.murphy (talk | contribs) at 21:55, 4 January 2007 (←Created page with 'In scuba diving, the '''rule of thirds''' is a rule of thumb that divers use to plan dives so they do not consume all the breathing gas from the [[divi...'). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.
In scuba diving, the rule of thirds is a rule of thumb that divers use to plan dives so they do not consume all the breathing gas from the diving cylinder before the end of the dive.
For divers following the rule, one third of the gas supply is planned for the outward journey, one third is for the return journey and one third is a safety reserve.
