What is the full O2 bottle pressure corrected for temperature?

• A. 1850 PSI
• B. 1500 PSI
• C. 2350 PSI
• D. 2000 PSI

Answer: (A)

Oxygen in a bottle behaves like a gas in a fixed-volume container, so its pressure changes with temperature according to the gas law P ∝ T (in Kelvin) when the amount of gas and the bottle volume stay the same. In aviation practice, a full O2 bottle is specified at a reference temperature of 70°F (21°C). At that temperature the pressure is about 1850 psi. The phrase “pressure corrected for temperature” means adjusting the pressure value to reflect the actual temperature using P2 = P1 × (T2/T1) with temperatures in Kelvin. Therefore, 1850 psi is the standard full-bottle pressure at the reference temperature, and is used as the corrected value. If the bottle were observed at a different temperature, you would scale that 1850 psi up or down accordingly—for example, at 0°C the pressure would be lower than 1850 psi, around 1700–1720 psi depending on the exact temperatures used.