How can you tell if cabin O2 is flowing on the 787?

How can you tell if cabin O2 is flowing on the 787?

• A. Red Oxygen Flow Indicator Light
• B. Green Oxygen Flow Indicator Light
• C. Amber Indicator Light
• D. No Indicator Visible

Answer: (B)

Oxygen flow is confirmed by a dedicated flow indicator that shows the system is actually delivering oxygen. On the 787, the green Oxygen Flow Indicator Light lights up to indicate that the cabin O2 is flowing. That color coding means normal operation with valves open and oxygen reaching the outlets. If the indicator were amber or red, it would signal a fault or reduced/no flow, and you’d need to follow abnormal procedures. If there’s no indicator visible when you expect flow, that would be inconsistent with normal operation. So, seeing the green light is the clear sign that cabin O2 is flowing.

Oxygen flow is confirmed by a dedicated flow indicator that shows the system is actually delivering oxygen. On the 787, the green Oxygen Flow Indicator Light lights up to indicate that the cabin O2 is flowing. That color coding means normal operation with valves open and oxygen reaching the outlets. If the indicator were amber or red, it would signal a fault or reduced/no flow, and you’d need to follow abnormal procedures. If there’s no indicator visible when you expect flow, that would be inconsistent with normal operation. So, seeing the green light is the clear sign that cabin O2 is flowing.