What is the minimum O2 pressure required for three crew members?

What is the minimum O2 pressure required for three crew members?

• A. 1000 PSI
• B. 1110 PSI
• C. 1200 PSI
• D. 1500 PSI

Answer: (B)

Oxygen supply must meet the needs of all crew members for a required duration after a depressurization. When three people are consuming oxygen, the total demand is higher, so the system must start with enough stored oxygen to last the full mandated time. The value 1110 psi represents the lowest pressure at which the system can still deliver the necessary flow to three crew for that duration. If the pressure drops below this, the supply would not meet the demand for all three. Pressures like 1200 or 1500 psi are more than enough, but they aren’t the minimum; 1000 psi would fall short of what’s needed for three.

Oxygen supply must meet the needs of all crew members for a required duration after a depressurization. When three people are consuming oxygen, the total demand is higher, so the system must start with enough stored oxygen to last the full mandated time. The value 1110 psi represents the lowest pressure at which the system can still deliver the necessary flow to three crew for that duration. If the pressure drops below this, the supply would not meet the demand for all three. Pressures like 1200 or 1500 psi are more than enough, but they aren’t the minimum; 1000 psi would fall short of what’s needed for three.