Which system delivers oxygen to crew and passengers in case of cabin depressurization?

• A. Oxygen systems on the A320.
• B. Fuel system.
• C. Hydraulic system.
• D. Environmental Control System.

Answer: (A)

When cabin pressure is lost, passengers and crew must have an immediate source of breathable oxygen. The aircraft provides this through its onboard oxygen systems, which are designed to deliver oxygen to all occupants via emergency masks and crew masks. On the A320, there are independent oxygen supplies for passengers (with chemical oxygen generators powering the masks) and for the crew’s masks in the cockpit, ensuring rapid, automatic delivery of oxygen as soon as depressurization occurs.

The Environmental Control System handles the conditioning, temperature, and distribution of cabin air under normal and pressurized conditions, but it does not supply the breathable oxygen required during a depressurization. The oxygen system is dedicated to providing the actual oxygen supply, separate from the ECS.