The Passenger Oxygen system is installed to provide oxygen during which condition?

The Passenger Oxygen system is installed to provide oxygen during which condition?

• A. Engine failure
• B. Decompression
• C. Smoke in cabin
• D. Cabin fire

Answer: (B)

When the cabin loses pressurization, the oxygen system is there to keep passengers breathing. A rapid decompression at altitude causes the cabin to rise in pressure, so automatic masks drop to provide breathable oxygen for a safe period while the aircraft descends to a breathable altitude and re‑pressurizes. This is the primary reason the passenger oxygen system exists. Engine failure by itself isn’t what triggers the passenger masks, and while smoke or a cabin fire are serious, the masks aren’t deployed for those conditions—the system is designed to address hypoxia from decompression.

When the cabin loses pressurization, the oxygen system is there to keep passengers breathing. A rapid decompression at altitude causes the cabin to rise in pressure, so automatic masks drop to provide breathable oxygen for a safe period while the aircraft descends to a breathable altitude and re‑pressurizes. This is the primary reason the passenger oxygen system exists. Engine failure by itself isn’t what triggers the passenger masks, and while smoke or a cabin fire are serious, the masks aren’t deployed for those conditions—the system is designed to address hypoxia from decompression.