Calculates the remaining oxygen and usable time from the cylinder capacity, pressure, and flow rate.
If the calculator does not appear, enable JavaScript and reload. The reference information and official links below still work.
Calculation basis and official references
Reviewed on:
This calculator is not a diagnosis, treatment plan, or prescription. Please consult a qualified clinician about your medical decisions.
Formula basis
When the pressure unit is MPa: remaining oxygen (L) = cylinder capacity (L) x pressure (MPa) x 10. When the unit is kgf/cm2: remaining oxygen (L) = cylinder capacity (L) x pressure (kgf/cm2). Usable time (min) = remaining oxygen (L) x safety factor / oxygen flow (L/min).
Calculation method
Calculates the remaining oxygen volume and usable time from the cylinder capacity, gauge pressure, safety factor, and oxygen flow rate.
Exclusions and checks required
The safety factor (default 0.8) is a practical margin to avoid fully depleting the cylinder; the actual margin used may vary by facility or patient condition.
This is a theoretical value; actual remaining gas varies with cylinder temperature, regulator condition, and wear, so always confirm with the actual gauge reading.
Results are truncated (rounded down) to a whole number, so the displayed value is always slightly lower than or equal to the true remaining amount (a safety-side rounding).
Example input:：3.4 L cylinder at 10 MPa with a flow rate of 2 L/min
size
3.4 L (approx. 500 L)
unit
MPa
pressure
10
safety
0.8
flow
2
The 136-minute usable time is a reference only; check and replace the cylinder early, allowing margin for travel time and emergencies.
Who is this calculator for? Oxygen Cylinder Remaining Capacity
Calculates the remaining oxygen and usable time from the cylinder capacity, pressure, and flow rate.
What values should I enter?
Applies to: Clinical practice
How should I interpret this estimate?
Calculates the remaining oxygen volume and usable time from the cylinder capacity, gauge pressure, safety factor, and oxygen flow rate.
How to use
Enter your input values and press Calculate.
Review the result and compare it with expected context.
When the pressure unit is MPa: remaining oxygen (L) = cylinder capacity (L) x pressure (MPa) x 10. When the unit is kgf/cm2: remaining oxygen (L) = cylinder capacity (L) x pressure (kgf/cm2). Usable time (min) = remaining oxygen (L) x safety factor / oxygen flow (L/min).