11.15 Oxygen Flashcards
What does EU-OPS 1.760 state?
Operator cant operate an aircraft above 25000ft with cabin crew unless its equipped with a supply of undiluted oxygen
What colour are oxygen bottles?
Green
What type of oxygen is suitable for use in aircraft?
Aviator’s breathing oxygen
What happens at 14000ft?
Oxygen masks are deployed
Where are the crew oxygen bottles located?
Lower deck
Where are oxygen bottles usually stored?
cargo compartment or Main Equipment Centre (MEC)
What is the pressure rating for high pressure oxygen bottles?
1800-1850psi
What pressure are oxygen bottles capable of maintaining up to?
2400psi
What did oxygen bottles used to be made off?
Steel
What are oxygen bottles now made of and why?
Aluminum wrapped in kevlar - lightweight
What periodic test must oxygen bottles undergo?
Hydrostatic testing
How do you figure out how full the bottle is and determine the maximum pressure for refilling?
Chart
What pressure does the overpressure safety disc discharge at?
2600psi
Why does every bottle need to be checked after the green safety disc discharges?
must find out which bottle triggered the discharge
What is the function of the manual slow opening Shut Off Valve (SOV) and where can it be located?
controls oxygen flow - on the cylinder head
What is the function of the direct reading pressure gauge and where can it be located?
indicates actual bottle pressure - near the filler port on the cylinder head
What is the function of the thermal compensator and where is it located?
distributes heat through a brush with a large surface area - connected to the filling line
What is the function of the overpressure burst disc and where is it located?
protects bottle against high pressure - connected to an overboard discharge line on the cylinder head
What is the function of the pressure regulator and where is it located?
decreases oxygen pressure to a suitable value - on the cylinder head
What is the function of the relief valve and where is it located?
in case pressure regulator fails - on the cylinder head
What is the function of the filling valve and where is it located?
allows bottle to be refilled - on the cylinder head
Where is portable oxygen equipment stored?
Cockpit & near exits
What is portable oxygen used for?
emergency and first aid
What are high pressure distribution lines made off?
stainless steel
What are low pressure distribution lines made off?
Aluminium
How is oxygen tubing identified?
Tape coding - labelled with green band stating ‘BREATHING OXYGEN’ & has white strip with black rectangles
What is the minimum amount of time smoke hoods must work for?
20 mins when physically active (factor of 3)
What is the minimum pressure for cylinders on a cart when oxygen charging?
50psi
What indicates a leak exists when using a soapy liquid for oxygen leak testing?
Bubbles
What are the 2 types of oxygen systems and who uses them?
Continuous flow (passengers & crew) & demand flow (flight crew)
What are the 2 types of demand flow oxygen systems & what is the difference?
diluter demand & pressure demand (both hold back flow until user inhales but pressure demand delivers high pressure oxygen via a pressure regulator
How can oxygen be reduced in a high oxygen pressure system?
2-step process & 1-step process?
What is a 2-step process?
- pressure reducer reduces pressure to intermediate level
- pressure regulator reduces pressure to useable level
How do you initiate oxygen flow in a continuous flow system?
Lanyard attached to mask is pulled
What does a manual release tool do and where is it inserted?
Stops release of masks when flight deck operate oxygen switch - slot of PSU door
What are the 2 supply systems?
chemical & gaseous
What are the 2 types of chemical systems and which is most common?
portable & fully integrated supplementary oxygen system (most common)
What are the stowage boxes known as in a chemical system & how are they deployed?
EOC (Emergency Oxygen Containers) - electrically by solenoid
What activates the oxygen in a chemical system and what is it filled with?
oxygen generator - sodium chlorate
What are the stowage boxes known as in a chemical system & how are they deployed?
PSU (Passenger Service Unit) - ring line
What activates the oxygen in a chemical system?
FCU (Flow Control Unit)
How many times can an oxygen generator be used, how can you tell its been used & can it be extinguished?
1 time, indicator on side of canister changes colour, no
What can you use to verify an oxygen system is functioning?
Flow indicator
