What must passengers onboard a pressurized AF aircraft at FL270 have access to for oxygen requirements?

At flight levels above 25,000 feet, such as FL270, it is essential that passengers have access to portable oxygen units. This requirement stems from the physiological effects of reduced atmospheric pressure at higher altitudes, which can lead to hypoxia if oxygen levels are insufficient.

Portable oxygen units provide essential supplemental oxygen to passengers in the event of cabin depressurization or if the aircraft is operating at altitudes where the ambient oxygen levels are inadequate for normal physiological function. These units typically come equipped with masks that passengers can wear to ensure they are receiving the necessary oxygen to maintain cognitive and physical performance during the flight.

While oxygen tanks stored in cargo or having extra oxygen outlets may provide some means of oxygen delivery, they would not adequately ensure immediate access for passengers in case of an emergency. A mask without oxygen would not serve a useful purpose in an altitude-related oxygen deficiency scenario, as it would not provide the needed oxygen supply. Therefore, portable oxygen units are the only option that effectively meets the requirement for passenger oxygen access at elevated flight levels.