Frequently asked questions

Javascript warning Javascript is a script language, which is suposed to run on Your computer. So those programs run offline in a sandbox.
If the Javascript standard is properly introduced into a computer system, it is not possible to make worms or viruses. So warnings on Javascript are warnings on a lousy implementation.
Pressure correction: The saturation of gases is dependent of the pressure of gas (for ideal gas: pV=nRT). Either the actual pressure of air or a more or less sophisticated barometric height function is used. The latter makes sense for the calculation of oxygen saturation in lakes, because there the time of contact of the parcel of water with the surface is unknown. So an averaged air pressure is used. For different sites on earth different functions should be used. 
Variables are latitude (acceleration), average temperature profile etc. Most sophisticated corrections are made by meterologists with their barometric correction to sea level, which is based on a high statistical smoothing of actual pressure data on the surface of earth. Aviatic use is another, rather long, story.
The more general functions are the US-standard atmosphere or the International standard atmosphere. For Swiss Lowlands a simple function was published by Schmassmann (it corrects for the common influence of the Alps).
As this Schmassmann curve is used in the oxygen calculator, this model has it's best precision in Switzerland. Elsewhere the results of general gas-calulator are better.
The atmospheric pressure varies with weather; so an error up to 5% saturation is probable for Swiss conditions.


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