Which two categories of onboard oxygen systems are commonly used in aircraft, and what are the associated safety concerns for each?

• A. Liquid oxygen systems with cryogenic hazards; chemical oxygen generators with heat hazards.
• B. Gaseous oxygen systems with no hazards; chemical oxygen generators with no hazards.
• C. Gaseous oxygen systems with no hazards; solid oxygen generators with no hazards.
• D. Compressed air systems with no hazards.

Answer: (B)