Three types of oxygen systems on all United aircrafts?

Three types of oxygen systems on all United aircrafts?

• A. Passenger, crew, and emergency
• B. Supplemental, first aid, and emergency
• C. Primary, secondary, and emergency
• D. Portable, fixed, and medical

Answer: (B)

Oxygen systems on an aircraft are defined by their purpose and how they’re used, not by who uses them. Supplemental oxygen provides a continuous supply to passengers and crew during altitude-related depressurization to keep everyone breathing normally. Emergency oxygen is the rapid-deployment system that kicks in during a sudden depressurization, ensuring immediate oxygen availability even if the cabin crew or passengers can’t reach other devices quickly. First aid oxygen refers to portable medical oxygen used for in-flight medical situations or by responders when a medical need arises. So the three categories that cover the usual in-flight oxygen setups are supplemental, first aid (medical), and emergency. Other options describe equipment types or user groups rather than distinct oxygen system categories, which is why they aren’t the best fit.

Oxygen systems on an aircraft are defined by their purpose and how they’re used, not by who uses them. Supplemental oxygen provides a continuous supply to passengers and crew during altitude-related depressurization to keep everyone breathing normally. Emergency oxygen is the rapid-deployment system that kicks in during a sudden depressurization, ensuring immediate oxygen availability even if the cabin crew or passengers can’t reach other devices quickly. First aid oxygen refers to portable medical oxygen used for in-flight medical situations or by responders when a medical need arises.

So the three categories that cover the usual in-flight oxygen setups are supplemental, first aid (medical), and emergency. Other options describe equipment types or user groups rather than distinct oxygen system categories, which is why they aren’t the best fit.