Removal of the Full-Face/Quick-Donning Oxygen-Mask

TASK 35-12-41-000-002-A
Removal of the Full-Face/Quick-Donning Oxygen-Mask

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.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

CAUTION: PUT DRY AND CLEAN METAL OR PLASTIC PLUGS ON ALL PIPES OR UNITS THAT YOU REMOVE TEMPORARILY. THEN PUT EACH PIPE OR UNIT IN A SEALED VINYL BAG. IF YOU DO NOT OBEY THESE INSTRUCTIONS, CONTAMINATION OF THE OXYGEN SYSTEM CAN OCCUR.

CAUTION: BE CAREFUL WHEN YOU DO MAINTENANCE OF THE FULL-FACE/QUICK-DONNING MASK(S). YOU CAN CAUSE DAMAGE TO THIS EQUIPMENT VERY EASILY IF YOU USE TOO MUCH FORCE OR THE INCORRECT CLEANING MATERIALS.

ZONE: 123
ZONE: 125
ZONE: 210
ZONE: 211
ZONE: 212
FIN: 5757HM
FIN: 5758HM
FIN: 5759HM
FIN: 5760HM

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	ACCESS PLATFORM 2M (6 FT)
No specific	AR	BAG - VINYL
No specific	AR	CAP - BLANKING
No specific	AR	PLUG - BLANKING, APPROVED FOR USE WITH OXYGEN
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.14TAE1)	Article-- Mask Film protection SAN 3
(Material No.14TAE2)	Article-- Mask Film protection SAN 6

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
123	NOSE GEAR WELL
125	LATERAL AVIONIC COMPARTMENT
210	CKPT,FWD COMPT BHD TO FLT COMPT BULKHEAD
211	COCKPIT
212	COCKPIT
812

D. Referenced Information

REFERENCE	DESIGNATION
TASK 24-42-00-861-001-A	Energize the Ground Service Network from the External Power
TASK 35-00-00-860-001-A	Special Precautions When Working on a Gaseous Oxygen System
Stowage of the Full-Face/Quick-Donning Oxygen Mask

3. Job Set-up
Subtask 35-12-41-010-056-A

A. Get Access
(1) Obey the special precautions when you do work on a gaseous oxygen system (Ref. AMM TASK 35-00-00-860-001).
(2) Put the ACCESS PLATFORM 2M (6 FT) in position at access door 812.
(3) Open access door 812.

Subtask 35-12-41-860-064-A ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Obey the special precautions when you do work on a gaseous oxygen system (Ref. AMM TASK 35-00-00-860-001).
(2) Energize the Ground Service Network from the External Power (Ref. AMM TASK 24-42-00-861-001).
(3) Fully close the valve of the oxygen storage cylinder (5750HM).
(4) Put a WARNING NOTICE(S) in position to tell persons not to open the valve of the oxygen storage cylinder.

Subtask 35-12-41-870-051-A ** ON A/C NOT FOR ALL

C. Bleeding of the two oxygen systems
(1) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:

Push the CREW SUPPLY pushbutton switch (the OFF legend goes off).

(2) On the Captain oxygen-mask stowage-box, push and hold the PRESS TO TEST AND RESET control button.
At the same time, push and hold the PRESS TO TEST/EMERGENCY knob on the mask regulator.
(a) Keep them pushed for a minimum of three seconds.

NOTE: During this time, the flow rate indicator changes from yellow to black and the volume of the sound of the oxygen flow decreases.

(b) When the flow rate indicator is black and when you no longer hear the sound of the oxygen flow:

Release the PRESS TO TEST/EMERGENCY knob.
Release the PRESS TO TEST AND RESET control button.

WARNING: MAKE SURE THAT THE PRESS TO TEST/EMERGENCY KNOB IS NOT IN THE EMERGENCY POSITION. IF IT IS IN THE EMERGENCY POSITION, THERE CAN BE A LEAK OF OXYGEN.

1 Make sure that the PRESS TO TEST/EMERGENCY knob is not in the EMERGENCY position.
(3) On the First-Officer oxygen-mask stowage-box, push and hold the PRESS TO TEST AND RESET control button.
At the same time, push and hold the PRESS TO TEST/EMERGENCY knob on the mask regulator.
(a) Keep them pushed for a minimum of three seconds.

NOTE: During this time, the flow rate indicator changes from yellow to black and the volume of the sound of the oxygen flow decreases.

(b) When the flow rate indicator is black and when you no longer hear the sound of the oxygen flow:

Release the PRESS TO TEST/EMERGENCY knob.
Release the PRESS TO TEST AND RESET control button.

WARNING: MAKE SURE THAT THE PRESS TO TEST/EMERGENCY KNOB IS NOT IN THE EMERGENCY POSITION. IF IT IS IN THE EMERGENCY POSITION, THERE CAN BE A LEAK OF OXYGEN.

1 Make sure that the PRESS TO TEST/EMERGENCY knob is not in the EMERGENCY position.
(4) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:

Release the CREW SUPPLY pushbutton switch (the OFF legend comes on).

Subtask 35-12-41-860-064-B ** ON A/C NOT FOR ALL

D. Aircraft Maintenance Configuration
(1) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:

Put a WARNING NOTICE(S) in position to tell persons not to push the CREW SUPPLY pushbutton switch.

(2) Energize the ground service network
(Ref. AMM TASK 24-42-00-861-001).
(3) Fully close the two manual-shutoff valves of the crew oxygen-storage cylinders (5750HM1 and 5750HM2).
(4) Put a WARNING NOTICE(S) in position to tell persons not to open the two manual-shutoff valves of the crew oxygen-storage cylinders (5750HM1 and 5750HM2).

Subtask 35-12-41-870-051-C ** ON A/C NOT FOR ALL

E. Bleeding of the two oxygen systems
(1) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:

Push the CREW SUPPLY pushbutton switch (the OFF legend goes off).

NOTE: During this time, the flow rate indicator changes from yellow to black and the volume of the sound of the oxygen flow decreases.

(b) When the flow rate indicator is black and when you no longer hear the sound of the oxygen flow:

Release the PRESS TO TEST/EMERGENCY knob.
Release the PRESS TO TEST AND RESET control button.

WARNING: MAKE SURE THAT THE PRESS TO TEST/EMERGENCY KNOB IS NOT IN THE EMERGENCY POSITION. IF IT IS IN THE EMERGENCY POSITION, THERE CAN BE A LEAK OF OXYGEN.

NOTE: During this time, the flow rate indicator changes from yellow to black and the volume of the sound of the oxygen flow decreases.

(b) When the flow rate indicator is black and when you no longer hear the sound of the oxygen flow:

Release the PRESS TO TEST/EMERGENCY knob.
Release the PRESS TO TEST AND RESET control button.

WARNING: MAKE SURE THAT THE PRESS TO TEST/EMERGENCY KNOB IS NOT IN THE EMERGENCY POSITION. IF IT IS IN THE EMERGENCY POSITION, THERE CAN BE A LEAK OF OXYGEN.

1 Make sure that the PRESS TO TEST/EMERGENCY knob is not in the EMERGENCY position.
(4) In the cockpit, on the OXYGEN section of the overhead control and indicating panel 21VU:

Release the CREW SUPPLY pushbutton switch (the OFF legend comes on).

Subtask 35-12-41-865-054-A

F. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	OXYGEN/CREW/OXY/SPLY	1HT	HA01

4. Procedure
Subtask 35-12-41-020-058-B

A. Removal of the Full-Face/Quick-Donning Oxygen-mask (5757HM, 5758HM, 5759HM, 5760HM)
(1) Open the doors of the stowage box (8).
(2) On the oxygen mask regulator (4), hold the oxygen mask (3) by its red harness-inflation control-plates (5) and remove it from its stowage box (8).
(3) Use the protection film on the internal and external surfaces of the oxygen mask window to prevent damage to the anti-mist layer:

For MF10 series, use the Article-- Mask Film protection SAN 3 (Material No.14TAE1)
For MF20 series, use the Article-- Mask Film protection SAN 6 (Material No.14TAE2) .

(4) Disconnect the electrical microphone connector (13) from its receptacle (9).
(5) Put a CAP - BLANKING on the disconnected electrical connector(s).
(6) Disconnect the quick-disconnect coupling (7) from its oxygen receptacle (10).
(7) Put a PLUG - BLANKING, APPROVED FOR USE WITH OXYGEN and a BAG - VINYL on the disconnected line ends.
(8) Put the oxygen mask (3) in a BAG - VINYL.
(9) In the cockpit, on the applicable stowage box (8):

Put a WARNING NOTICE(S) in position to tell persons that you removed the related oxygen mask from its stowage box (8).

[Rev.10 from 2021] 2026.04.01 04:14:34 UTC