"Pressure"
1. Standard sea level pressures are given in various units at a
temperature of 59 degs.
2. 29.92 inches of mercury.
3. 1013.2 millibars.
4. 14.7 lbs. per square inch.
"Standard Heights Above The Sea Level"
1. 1,000 MB = Surface 5. 400 MB = 23,000 ft.
2. 850 MB = 5,000 ft. 6. 300 MB = 30.000 ft.
3. 700 MB = 10,000 ft. 7. 200 MB = 40.000 ft.
4. 500 MB = 18,000 Ft.
1. At 18,000 feet, 500 MB. half the atmosphere is below.
2. The human body functions best with the amount of oxygen supplied
under normal pressure, about 1,000 millibars.
3. The total pressure is 200 millibars of oxygen pressure. About 800
millibars of Nitrogen.
4. Insufficent supply of Oxygen results in irreparable damage to
the brain.
5. Flights abovt 15,000 feet, and prolonged flights above 10,000 feet,
should not be made without oxygen.
6. A properly regulated supply of Oxygen is such that the Oxygen
pressure will amount to 200 millibars.
7. This is accomplished by displacing part or all of the Nitrogen
normally in the air with the Oxygen.
8. At about 18,000 feet when the total pressure is 500 Millibars, the
proper mixture would be 200 millibars of Oxygen, 300 millibars of
nitrogen, or 2/5 Oxygen.
9. At 200 millibars, 40,000 feet, pure Oxygen would have to be used.
1. A BAROMETER is used to measure air pressure.
2. An ALTIMETER is used to measure heights in feet above the ground.
"Weather By Giannetta"
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