Detailed Inspection of the Oxygen Masks

TASK 35-21-00-210-003-A
Detailed Inspection of the Oxygen Masks

WARNING: KEEP ALL HYDROCARBONS (FUELS, LUBRICANTS, ETC.) AWAY FROM ALL SOURCE OF OXYGEN. OXYGEN BECOMES EXPLOSIVE WHEN IT TOUCHES HYDROCARBONS.

WARNING: CLEAN THE TOOLS AND MAKE SURE YOUR HANDS ARE CLEAN TO PREVENT CONTAMINATION OF THE OXYGEN SYSTEM.

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	WARNING NOTICE(S)
995000-00	1	TOOL-MANUAL RELEASE

B. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 35-00-00-860-001-A	Special Precautions When Working on a Gaseous Oxygen System
TASK 35-21-42-400-001-A	Installation of the Emergency Oxygen Generators
TASK 35-21-43-550-801-A	Packing of the Oxygen Mask Assemblies
Emergency Oxygen Container (Chemical) - Example

3. Job Set-up
Subtask 35-21-00-861-060-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Obey the special precautions when you work on a gaseous oxygen system (Ref. AMM TASK 35-00-00-860-001).
(2) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(3) In the cockpit, on the OXYGEN section of overhead panel 21VU:
(a) Put a WARNING NOTICE(S) in position to tell persons not to operate the emergency oxygen system.

Subtask 35-21-00-010-069-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Put the 995000-00 TOOL-MANUAL RELEASE into the access hole in the applicable door.

NOTE: It is permitted to use alternative tool P/N 995000.

(2) Push the tool in until the latch is released. The door opens and the masks fall out.

4. Procedure
Subtask 35-21-00-210-056-A ** ON A/C NOT FOR ALL

A. Detailed Visual Inspection of the Oxygen Masks (Chemical)

CAUTION: DO NOT PULL THE MASK LANYARD FROM THE END WITH THE RELEASE PIN. IF YOU PULL ON THIS END OF THE LANYARD, YOU WILL REMOVE THE RELEASE PIN AND START A FLOW OF OXYGEN WHICH CANNOT BE STOPPED.

CAUTION: IF THE EMERGENCY OXYGEN CONTAINER IS INSTALLED NEAR A CURTAIN RAIL, MAKE SURE THAT THE EMERGENCY OXYGEN CONTAINER AND THE CURTAIN RAIL ARE INSTALLED CORRECTLY. IF THEY ARE NOT INSTALLED CORRECTLY, IT IS POSSIBLE THAT THE MASKS WILL NOT FALL OUT CORRECTLY IN AN EMERGENCY.

(1) Examine the oxygen masks and the flexible supply hoses for cracks, dirt and changes in color.

WARNING: MAKE SURE THAT THE FLEXIBLE HOSES ARE IN THE CORRECT CONDITION. IF THEY ARE TWISTED, DAMAGED, DEFORMED OR INCORRECTLY INSTALLED, OXYGEN CANNOT FLOW THROUGH THE HOSES OR A LEAK CAN OCCUR.

(2) Examine the flexible supply hoses to make sure that they are correctly connected to the reservoir bags and the emergency oxygen generators.
(3) Examine the reservoir bags to make sure that there are no tears and that they are correctly connected to the masks. Make sure that you can read all the legends.
(4) Examine the elastic headbands for over-extension and elasticity to make sure that they are correctly attached to the masks.
(5) Do a check of the lanyards:
(a) Give the lanyard to mask connection a strong, short pull to make sure that the connection is satisfactory:
1 Make sure that the lanyards are free and are not caught on the other parts of the emergency oxygen container.
(6) Examine the foam pads of the emergency oxygen generators for the correct installation (Ref. AMM TASK 35-21-42-400-001).

NOTE: This step is necessary only when the oxygen containers with the part numbers that follow are installed:

1XC15XXXXXX0000 and 0003
1XC22XXXXXX0004 and 0005
22C15XXXXXXXXXX
22C22XXXXXXXXXX.

5. Close-up
Subtask 35-21-00-530-050-A ** ON A/C NOT FOR ALL

A. Packing of the Oxygen Masks in the Oxygen Containers
(1) Put the oxygen masks into the oxygen containers (Ref. AMM TASK 35-21-43-550-801).

Subtask 35-21-00-862-060-A ** ON A/C NOT FOR ALL

B. Put the aircraft back to its initial configuration.
(1) In the cockpit, on the OXYGEN section of overhead panel 21VU:
(a) Remove the WARNING NOTICE(S).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 01:04:52 UTC