What are the two types of fixed oxygen systems on board an aircraft?

The two types of fixed oxygen systems on board an aircraft are gaseous and generator-based systems. Gaseous oxygen systems utilize compressed oxygen that is stored in high-pressure cylinders and is released through masks during emergencies. This system is commonly used in commercial aviation because of its simplicity and reliability.

Generator-based oxygen systems, on the other hand, produce oxygen through a chemical reaction when activated. This type of system is often lighter than gaseous systems and can provide a continuous supply of oxygen, making it suitable for certain aircraft types or specific operational needs.

Understanding the distinction between these two systems is crucial for safety protocols, as each system operates differently and serves unique purposes in maintaining passenger and crew safety during in-flight emergencies.