What kind of emergency oxygen system is found on the Boeing 787?

• A. Chemical
• B. Gaseous
• C. Liquid
• D. Hybrid

Answer: (B)

The concept being tested is the type of emergency oxygen system used on modern airliners. The Boeing 787 uses a gaseous oxygen system. Instead of generating oxygen on demand with chemical reactions, it stores compressed oxygen in onboard tanks and distributes it to passengers through masks as soon as the system is activated. This approach provides immediate, reliable oxygen without the heat and fire hazards associated with chemical generators, and it meets regulatory requirements for the duration of supply.

Chemical oxygen generators—common on older aircraft—produce oxygen through a chemical reaction, but they generate heat and require ongoing maintenance and safety considerations. Liquid oxygen would require cryogenic storage and additional hardware, making it impractical for typical passenger aircraft. A hybrid system would mix characteristics of different methods, but the 787’s design chose the straightforward, safer option of gaseous oxygen.