-3 Barometric Valve Automatic Function

Barometric Valve Automatic Function

1. 
   Manual deployment system is operative,
   
2. 
   Flight remains at or below FL 300, and
   
3. 
   Passenger supply valve is operative.
   

1. 
   Make sure the oxygen cylinders are fully charged and cylinder stop valves are open.
   
2. 
   Open the passenger oxygen supply valve.
   
3. 
   Select OVERRIDE on the oxygen control panel, on pilot’s side panel.
   
4. 
   Make sure all drop out mask boxes have opened and all masks are hanging from lanyard cord.
   

Oxygen pressure remaining inside the cabin oxygen lines must be decreased before repacking mask.

5. 
   Reset the cabin oxygen manual override knob.
   
6. 
   Decrease remaining oxygen pressure at each deployed mask box by pulling the lanyard cord which removes the lanyard pin from the valve.
   
7. 
   Let the inlet oxygen pressure exhaust, and install the lanyard pin into the valve.
   
8. 
   Carefully restow all deployed masks.
   
9. 
   Place placard MAX FL 300 on instrument panel.
   

Protective Breathing Equipment (PBE)

Passenger Oxygen Masks and Stowages

1. 
   Block and placard any seat with an inoperative mask to prevent occupancy, and
   
2. 
   Brief passengers not to occupy affected seats.
   

1. 
   Flight is not conducted where the minimum enroute altitude is above 14,000 feet MSL,
   
2. 
   Pressurization system is operative,
   
3. 
   Flight remains at or below FL 250,
   
4. 
   Portable oxygen is provided to each passenger above 15,000 feet MSL, and
   
5. 
   Passengers are appropriately briefed.
   

1. 
   Make sure all components of the pressurization system operate normally.
   
2. 
   Place placard MAX FL 250 on instrument panel.
   
3. 
   Flight is not to be conducted where the MEA is above 14,000 feet MSL,
   
4. 
   Flight to be conducted at or below FL 250.
   
5. 
   Provide portable oxygen to each passenger above 15,000 feet MSL,
   
6. 
   Brief passengers.
   

Portable Oxygen Dispensing Unit

1. 
   Required distribution of serviceable bottles is maintained throughout the aircraft, and
   
2. 
   Bottles not properly serviced are replaced, serviced or removed at the next available maintenance facility.
   

1. 
   Bottles not properly serviced are to be replaced, serviced or removed at the next available maintenance facility.
   
2. 
   Bottle is to be secured in its original housing and placarded as inoperative and empty.