Flight Crew Oxygen System
The flight crew oxygen system uses quick-donning, diluter-demand masks/
regulators located at each crew station. Oxygen is supplied by a single
Oxygen pressure is displayed on the Oxygen Pressure indicator located
overhead panel when the battery switch is ON. Oxygen flow is controlled
an in-line, pressure-reducing regulator to supply low-pressure oxygen
regulator on the mask. Minimum pressure for dispatch is variable by temperature
and additional flight deck crew . System pressure may be as high as 1850 psi.
Passenger Oxygen System
The passenger oxygen system is supplied by individual chemical oxygen
generators located at each Passenger Service Unit (PSU). Four continuous flow
masks are connected to each generator. A generator with two masks is located
above each attendant station and in each lavatory.
The system is activated automatically by a pressure switch at a cabin altitude of
approximately 14,000 feet or when the Passenger Oxygen Switch on the aft
overhead panel is positioned to ON. When the system is activated, the PASS OXY
ON light illuminates and OVERHEAD illuminates on the Master Caution System.
When the High Altitude Landing Switch [Option], located on the Cabin Altitude
Panel, is placed in the ON position the cabin altitude warning horn is reprogramed
from 10,000 feet to 14,000 feet and automatic oxygen mask activation is
reprogramed to 14,650 feet.
Activating the system causes the masks to drop from the stowage compartments.
The oxygen generators are activated when any mask in the unit is pulled down.
Pulling one mask down causes all masks in that unit to come down and 100%
oxygen flows to all masks. A green in–line flow indicator is visible in the
transparent oxygen hose whenever oxygen is flowing to the mask. Oxygen flows
for approximately 12 minutes and cannot be shut off. If the passenger oxygen is
activated and a PSU oxygen mask compartment does not open, the masks may
be dropped manually.
The flight crew oxygen system uses quick-donning, diluter-demand masks/
regulators located at each crew station. Oxygen is supplied by a single
Oxygen pressure is displayed on the Oxygen Pressure indicator located
overhead panel when the battery switch is ON. Oxygen flow is controlled
an in-line, pressure-reducing regulator to supply low-pressure oxygen
regulator on the mask. Minimum pressure for dispatch is variable by temperature
and additional flight deck crew . System pressure may be as high as 1850 psi.
Passenger Oxygen System
The passenger oxygen system is supplied by individual chemical oxygen
generators located at each Passenger Service Unit (PSU). Four continuous flow
masks are connected to each generator. A generator with two masks is located
above each attendant station and in each lavatory.
The system is activated automatically by a pressure switch at a cabin altitude of
approximately 14,000 feet or when the Passenger Oxygen Switch on the aft
overhead panel is positioned to ON. When the system is activated, the PASS OXY
ON light illuminates and OVERHEAD illuminates on the Master Caution System.
When the High Altitude Landing Switch [Option], located on the Cabin Altitude
Panel, is placed in the ON position the cabin altitude warning horn is reprogramed
from 10,000 feet to 14,000 feet and automatic oxygen mask activation is
reprogramed to 14,650 feet.
Activating the system causes the masks to drop from the stowage compartments.
The oxygen generators are activated when any mask in the unit is pulled down.
Pulling one mask down causes all masks in that unit to come down and 100%
oxygen flows to all masks. A green in–line flow indicator is visible in the
transparent oxygen hose whenever oxygen is flowing to the mask. Oxygen flows
for approximately 12 minutes and cannot be shut off. If the passenger oxygen is
activated and a PSU oxygen mask compartment does not open, the masks may
be dropped manually.
