Calculate how long an oxygen cylinder will last based on tank pressure, flow rate, and cylinder type. Essential for medical professionals and patients managing oxygen therapy.
Last updated: March 2026
Disclaimer: This calculator provides duration estimates and assumes a 500 PSI safety reserve. Actual duration depends on regulator type, temperature, altitude, and equipment condition. Never rely on this tool for clinical oxygen management.
Always maintain a safety margin and replace tanks before complete depletion. For medical oxygen therapy, follow prescriptions and equipment guidelines provided by healthcare providers and oxygen suppliers. In emergencies, call emergency services immediately.
⚠ Safety Reminder: Always maintain a safety margin. Replace or refill tanks before they run out.
Oxygen tank duration refers to how long a compressed oxygen cylinder will last at a given flow rate. This is critical for patients on supplemental oxygen therapy, emergency medical services, and healthcare facilities to ensure continuous oxygen supply.
The duration depends on three factors: the cylinder size (tank factor), the current pressure in PSI, and the flow rate in liters per minute. Different cylinder sizes have different tank factors, which represent the volume of oxygen they can hold per PSI.
Understanding tank duration helps in planning trips, ensuring backup supplies, and preventing dangerous situations where oxygen supply runs out unexpectedly. Always maintain a safety margin and replace tanks before complete depletion.
Calculate duration for an E cylinder at 2000 PSI with 2 L/min flow:
The E cylinder will last approximately 4 hours and 40 minutes at 2 L/min.
The calculation provides a theoretical duration based on ideal conditions. Actual duration may vary slightly due to temperature, altitude, regulator efficiency, and gauge accuracy. Always plan for 10-20% less time as a safety margin.
Never let a tank fully deplete. Replace or refill when pressure drops to 500 PSI (or 200 PSI for some systems). Running a tank completely empty can damage the regulator and introduce contaminants into the system.
Yes, flow rate can be adjusted based on patient needs and physician orders. Higher flow rates provide more oxygen but deplete the tank faster. Always follow prescribed flow rates and consult healthcare providers before changes.
Cylinder types differ in size and portability. D and E cylinders are portable (E is most common for home use and ambulances). M cylinders are medium-sized with wheels. H/K cylinders are large stationary tanks for facilities or backup home use.
Tank gauges show PSI (pounds per square inch). A full tank typically reads 2000-2200 PSI. The gauge should be checked before each use and monitored during use to prevent running out unexpectedly.
Main factors: cylinder size (tank factor), current PSI, and flow rate. Secondary factors include temperature (cold reduces pressure readings), altitude (higher altitude affects delivery), and regulator condition. Leaks can also dramatically reduce duration.
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