O2 Oxygen Requirements Flashcards
At what altitudes do different oxygen requirements start?
Part 91.211 (General)
1) 12,500
2) 14,000
3) 15,000
Part 91.211 (Pressurized Aircraft)
1) FL250
2) FL350
What are the O2 requirements when flying between 12,500’ and 14,000’?
An aircraft is allowed to operate between 12,500 and 14,000’ for a maximum of 30 minutes during a flight without supplemental O2.
When longer than 30 minutes, the ‘minimum flight crew’ is required to use O2 for that duration.
NOTE: This is the entire flight. You cannot dip down below 12,500’ to reset your time.
What are the O2 requirements when flying between 14,000’ and 15,000’?
When flying at these altitudes, all required crew is required to use supplemental O2 requirements.
What are the O2 requirements when flying above 15,000’?
All required flight crew needs to use O2 during all flight above 15,000’. In addition, all passengers must be offered supplemental O2.
The passengers do not have to use the O2.
What are the O2 requirements when operating a pressurized aircraft above FL250?
A 10-minute supply of supplemental O2 is required for each occupant of the flight.
What are the O2 requirements when operating a pressurized aircraft above FL350?
One pilot must wear a secured and sealed O2 mask at all times, that either constantly provides O2, or automatically provides O2 if the cabin pressure exceeds 14,000’.
Unless two pilots each have a quick-donning type mask, and the flight is below FL410.
Regardless of altitude, or mask-type availability, if one pilot leaves their duty station above FL350, the remaining pilot must be wearing their O2 mask for that duration.
What are the four types of supplement O2 storage/delivery systems?
1) Gaseous Aviator’s Breathing Oxygen (ABO)
2) Liquid Aviators Breathing Oxygen (LOX)
3) Sodium Chlorate Candles (Solid-State Oxygen)
4) Molecular Sieve Oxygen Generators (MSOG)
How does Gaseous Aviator’s Breathing Oxygen work?
This is the most common systems in General Aviation. This is O2 stored in pressurized tanks. The tanks can be high pressure, or low pressure. Tanks must be filled with Aviation Breathers Oxygen (ABO), and not any other type of O2.
How does Liquid Aviators breathing oxygen work?
This oxygen is also stored in tanks. But it is cooled to its liquid state at -197°. Storing at this temperature is very hard, and is very volatile when coming in contact with petroleum products. It is great for space saving. If LOX comes into contact with human skin, it may cause frostbite.
How does Sodium Chlorate Candles (solid-state oxygen) work? (Oxygen Candles)
Oxygen candles work by heating Sodium Chlorate. When this chemical burns, it produces oxygen. This reaction occurs at 350°, and caution must be taken. There are large weight savings with this method, as the candles are small and can be stored easily. Once they are burning, they are difficult to stop, using the potential for fire hazards.
How do Molecular Sieve Oxygen Generators (MSOG) work?
This system takes the ambient air, and separates the O2 from it. The separated O2 is then used to supply the aircraft. This is more common in the military, as well as medical patients. Not common for general aviation.
What are the different types of Oxygen Delivery Systems?
1) Continuous Flow
2) Diluter Demand
3) Pressure Demand
How does the Continuous Flow oxygen system work?
As the title suggests, this system continually provides a flow of oxygen. This is an easy system to implement, as it is either on or off. However it is wasteful, as the O2 is always flowing when on.
What altitudes is the Continuous Flow system good for?
This system is good for altitudes of 28,000’ and lower.
How does the Diluter Demand system work?
This system was designed for the shortcomings of the continuous flow system. This system provides on-demand oxygen. It only provides oxygen when a breath is being taken, and stops otherwise. This helps preserve oxygen.
This system also adjusts the amount of O2 being produced, depending on the altitude. This provides the right ratio of O2 being breathed in.
