Oxygen System Preflight Check

A preflight check of the oxygen system in an aircraft ensures the system is functional and ready for use in case of an emergency, involving verifying pressure, regulator function, indicators, connections, and emergency procedures.

Here's a more detailed breakdown of what's typically involved in an oxygen system preflight check:

1. Pressure

Check oxygen cylinder pressure: Ensure there's sufficient oxygen pressure for the planned flight duration and altitude.

Verify pressure indicators: Confirm that the pressure gauges or indicators are functioning correctly and show adequate pressure.

2. Regulator

• Inspect the regulator: Check for any damage or signs of malfunction.
• Test regulator function: Open the oxygen valves and test the mask test button or paddles to ensure a hissing sound, partial inflation of the harness, and the blinker indicating flow.

3. Indicators

Check oxygen flow indicators: Ensure that the oxygen flow indicators are functioning correctly and show a steady flow of oxygen.

Verify blinker function: Confirm that the blinker indicates flow when the mask test button is pressed.

4. Connections

Ensure all connections are secure: Check oxygen lines, plug-in couplings, and mask connections to ensure they are properly secured.

Inspect masks and cannulas: Verify that the masks or cannulas are in serviceable condition and properly connected.

5. Emergency

• Ensure oxygen equipment is readily available: Have oxygen equipment in the cockpit ready for use in emergencies.
• Brief passengers (if applicable): Brief passengers on the location of oxygen masks and their proper use.
• Check for emergency oxygen panel: Verify the emergency oxygen panel is functional and allows for manual deployment of passenger oxygen masks if necessary.
• Check for overboard discharge port: Ensure the green disk in the overboard discharge port is in place and easily seen.