Smoke Hood Operation Figure 002 
R  EFF : 106-149, 151-199, 201-299, 301-399, 401-499,  Page 535-31-00Config-2 Aug 01/05
 CES 

 FLIGHT CREW PORTABLE DEVICES - DESCRIPTION AND OPERATION
________________________________________________________
 1.
 General

_______ The flight crew emergency breathing hood system provides protection to the eyes and respiratory system for crew members. It is used when fighting a fire, against the emission of smoke and noxious gas. The breathing hood makes sure that the crew has an air supply of more than 20 minutes.

 2.
 Description

___________
 A. Breathing Hood System
 (1)
 Component Location (Ref. Fig. 001) The breathing hood container is installed in the cockpit in the Raft Console 702VU. The container is provided with a good-condition indicator and tamper seal used for the preflight inspection.

 (2)
 Storage The complete hood is vacuum-packed in a transport/storage container. The breathing hood is stored under vacuum in a specially designed sachet. The sachet is mounted inside a box in such a way that, after opening the box, the hood is removed and the vacuum protection is automatically opened with a single movement.

 (3)
 Box Description This box made of a polycarbonate is composed of two parts (cover and container) equipped with:

 -
a good-condition indicator on the lid (operational color: yellow)

 -
a handle

 -
a hinge for jointing the container and the cover

 -
a pictogram which describes the utilization procedure

 -an identification plate, located at the back of the container which gives the date of its manufacture. To gain access to the aluminized bag it is necessary to break the lead seal and open the box cover.
R EFF : 001-049, 055-061, 101-105, 35-31-00Page 1

 Breathing Hood Container
 Figure 001

R EFF : 001-049, 055-061, 101-105, 35-31-00Page 2 Config-3 May 01/05
 CES

 B. Description of the Protective Breathing Equipment (Ref. Fig. 002) The protective breathing equipment is composed of three main parts:
 (1)
 A hood The hood is provided with: -the collar seal at the level of the neck. -the straps attached to the hood maintains the oronasal (or inner) mask around the back of the user head. -a relief valve in the hood which keeps the overpressure in the hood at a comfortable level.

 (2)
 The oronasal (or inner) mask The oronasal mask is provided with: -an anti-suffocation valve, operated by a higher breathing resistance. The user can inhale through this valve from the volume between head and hood. In case of empty breathing bag, however this makes it possible to inhale from the outside closed-loop breathing system without lifting the mask or doffing the hood.

 -A speech transmitter is located in front of the oronasal mask.

 (3)
 A KO2 cartridge.
 This cartridge is provided with:

 -An attached breathing bag equipped with a volume-controlled relief valve. This valve keeps the breathing resistance for exhalation on the low level even in case of a filled breathing bag.
 -
A starter activated by a lanyard.

 -
A fold tube (or breathing hose) for the liaison with the oronasal mask.

 -
A belt which holds the cartridge on the hood.

 (4)
 The technical characteristics are:

 -Duration: more than 20 minutes.
 -Bag capacity: 6 l (NTPD)
 -Operational temperature: -10.C to +50. C.
 3. Operation/Control and Indicating
________________________________
 A. Operation (Ref. Fig. 003) The protective breathing hood works with a closed breathing circuit. The expired air will be regenerated, enriched with oxygen, and inhaled again. The oxygen is generated in exothermic chemical reaction between the potassium piroxide (KO2), the humidity, and the carbon dioxide (CO2) in the expired air. This reaction releases heat.
R EFF : 001-049, 055-061, 101-105, 35-31-00Page 3

 Breathing Hood Figure 002 
R  EFF :  001-049, 055-061, 101-105,  Page 435-31-00 Config-3 May 01/05
 CES 

 General Operation Figure 003 
R  EFF :  001-049, 055-061, 101-105,  Page 535-31-00 Config-3 May 01/05
 CES 

 B. Donning sequence (Ref. Fig. 004)
 C. Indicating If the yellow indicator inside the box shows the serviceability of the breathing hood, in addition the tamper seal indicates that the container has not been opened. If the yellow indicator is not apparent or if the tamper seal is broken the protective breathing equipment must be replaced.
　
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：A320飛機維護手冊 AMM OXYGEN 氧氣(166)