What should beginners know about gas consumption?

Every diver uses gas at a different rate, and beginners almost always go through it faster than they expect. Gas consumption depends on depth, breathing style, and how relaxed you are in the water. The deeper you go, the denser the gas becomes, so each breath delivers more gas molecules even though the volume feels the same. Nervous movement, poor trim, or rapid breathing also use gas more quickly. With experience, breathing slows down, movements become smoother, and dives last longer.

Good gas management is about awareness, not restriction. You should not try to change your breathing to match a dive plan. You change the plan to match your breathing. And you should not compare yourself to other divers. Larger people will generally use more gas per minute than smaller ones, and experienced divers often use less, but not always. Every diver’s body and breathing rhythm are different. Focus on understanding your own gas use and planning dives that fit it.

Recreational Gas Planning Guide for Open Water Divers

Practical recreational gas planning: RMV basics, Minimum Gas Reserve, and turn pressure methods. Equations and examples included.

Minimum Gas Reserve | CAT Formula with Worked Example

Calculate your minimum gas reserve with the CAT formula. 100 ft example, ATA math, AL80 PSI conversion, and why divers round up for safety.

RMV Calculator

Calculate your RMV (Respiratory Minute Volume) and SAC rate. Includes formulas, step-by-step breakdowns, and a reference table of common scuba tanks.