What is the recommended cylinder pressure (psig) for oxygen delivery?

• A. 900 psig
• B. 1000 psig
• C. 1200 psig
• D. 1500 psig

Answer: (B)

Oxygen cylinders are a high‑pressure gas source, and knowing how much gas remains is tied to the cylinder’s pressure. The practical minimum you use for continuing reliable delivery is about 1000 psig. Full oxygen cylinders are around 2000 psig, so when the pressure gauge reads roughly half, you have about half the gas left. That half provides a comfortable safety margin to complete the current case or switch to a new cylinder before you risk running out, even if you encounter a longer-than-expected case or a temporary regulator issue.

Choosing 1000 psig balances the need to avoid interruptions with the practicality of timely cylinder changes. A reading near 900 psig leaves less gas and increases risk of depletion during ongoing anesthesia, while numbers like 1200 or 1500 psig imply you’re waiting for more gas than is routinely necessary to maintain safe, continuous delivery.