Airway & Oxygen

Oxygen Cylinder Duration Calculator

How long a cylinder will last at a given flow.

Reviewed by Alex G, BSN, RN, CEN, CCRN, CMC, NREMT-P · From the Reference tab of the app

Turn on JavaScript to use this calculator, or open it in the web app.

Formula

Minutes = (gauge psi − 200 safe residual) × cylinder constant ÷ flow (L/min)

How it is used

• Constants: D 0.16, E 0.28, M 1.56, G 2.41, H/K 3.14 L per psi.
• A full D cylinder (about 2,000 psi) lasts under 20 minutes at 15 L/min; switch to the onboard supply for transport and carry a spare on long calls.

Same formula as the app. Open it in the web app.

Related one-pagers

• Equipment, Gas Supply and Patient DataDuration · Minutes = psi × cylinder factor ÷ L/min (E factor 0.28; others on PFTs and Oxygen Delivery)
• Airway and RSI
• PFTs and Oxygen Delivery

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For education and exam preparation only. Follow your institution’s protocols. For education and exam preparation only. Verify results independently and follow your institution’s protocols. Not a substitute for clinical judgment.