formulas to check pressure at hight altitud
by Jaiem Mendoza
(New york USA.)
High Pressure Measurements
I need to set up an air compressor at ground level and run an air hose 200 feet height. What is the air pressure change at that height?
- How much less will the air pressure outside the hose at 200 feet than it be will be at the compressor level?
If that's the case, you can use a standard atmosphere calculator like the one at:
It has the formulas to check pressure built right in.
From Sea level to 200 feet, the outside atmospheric pressure drops
from 101325 Pa to 100595 Pa, a difference of 730 Pascals, a drop of about 0.7 %
The two hundred feet won't make much difference. One can expect a similar change to occur inside the hose from one end to the other as well.
Running through similar calculations to the one above gives changes of our 200 feet starting from various elevations from -2000 to 85000 metres. The result obtained using the numbers provided by the website referred to above ranged from approximately 0.3 % for very high elevations to 1 % for intermediate elevations (in the stratosphere).
The amount of percentage change depends on a number of things, the most obvious being atmospheric composition (changes in humidity, mostly) and the convective / stratification
characteristics of the atmospheric layer
this site for more information now.