Free gas volume ≈ water capacity (L) × gauge pressure (bar). 1 kg/cm² ≈ 0.98 bar; 1 bar ≈ 14.5 psi.
L
bar
Oxygen contents
1500 L
Use o2-cylinder-duration with your flow rate
Under 300 L: replace before transfer
Use o2-cylinder-duration with your flow rate
Formula
water * pressure
Notes
Ignores gas compressibility (slight overestimate at high pressure). Gauges in kg/cm² read almost the same as bar; psi ÷ 14.5 = bar.Calculators support, not replace, clinical judgement. Check inputs and units, and confirm doses with your unit protocol.