CS 25.1439 Protective breathing equipment

ED Decision 2007/020/R

(a)     Fixed (stationary, or built in) protective breathing equipment must be installed for the use of the flight crew, and at least one portable protective breathing equipment shall be located at or near the flight deck for use by a flight crew member. In addition, portable protective breathing equipment must be installed for the use of appropriate crew members for fighting fires in compartments accessible in flight other than the flight deck. This includes isolated compartments and upper and lower lobe galleys, in which crew member occupancy is permitted during flight. Equipment must be installed for the maximum number of crew members expected to be in the area during any operation.

(b)     For protective breathing equipment required by subparagraph (a) of this paragraph or by the applicable Operating Regulations, the following apply:

(1)     The equipment must be designed to protect the appropriate crewmember from smoke, carbon dioxide, and other harmful gases while on flight deck duty or while combating fires.

(2)     The equipment must include –

(i)      Masks covering the eyes, nose and mouth, or

(ii)     Masks covering the nose and mouth, plus accessory equipment to cover the eyes.

(3)     Equipment, including portable equipment, while in use must allow communication with other crew members while in use. Equipment available at flight crew assigned duty stations must enable the flight crew to use radio equipment.

(4)     The part of the equipment protecting the eyes must not cause any appreciable adverse effect on vision and must allow corrective glasses to be worn.

(5)     The equipment must supply protective oxygen of 15 minutes duration per crew member at a pressure altitude of 2438 m (8000 ft) with a respiratory minute volume of 30 litres per minute BTPD. The equipment and system must be designed to prevent any inward leakage to the inside of the device and prevent any outward leakage causing any significant increase in the oxygen content of the local ambient atmosphere. If a demand oxygen system is used, a supply of 300 litres of free oxygen at 21°C (70°F) and 760 mm Hg pressure is considered to be of 15-minute duration at the prescribed altitude and minute volume. If a continuous flow open circuit protective breathing system is used a flow rate of 60 litres per minute at 2438 m (8 000 ft) (45 litres per minute at sea level) and a supply of 600 litres of free oxygen at 21°C (70°F) and 204 kPa (760 mm Hg) pressure is considered to be of 15-minute duration at the prescribed altitude and minute volume. Continuous flow systems must not increase the ambient oxygen content of the local atmosphere above that of demand systems. BTPD refers to body temperature conditions, that is 37°C (99°F), at ambient pressure, dry.

(6)     The equipment must meet the requirements of CS 25.1441.

[Amdt 25/4]