Michell Humidity Calculator Settings

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Result units

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Known Parameter
The humidity parameter that is known. e.g. Dew Point

Known Value
The value of the known parameter.

Known Units
The unit of measurement of the known parameter. e.g °C

Sample Pressure
The pressure at the point where the humidity measurement is made. Defaults to atmospheric pressure.

Pressure Units
The unit of measurement of the sample pressure. e.g. Pascals

Pressure Compensation
If conversion to another pressure is required, enter that pressure in this box. The measurement units will be the same used for the Sample Pressure.

Gas Type
Choose from a list of preset molecular weights. Used only for ppmW & mixing ratio calculations. A user-defined molecular weight can be entered by selecting 'User'.

Mol. Weight
Molecular weight of gas being measured, used only for ppmW/Mixing Ratio calculations.

Sample Temperature
The temperature at the point where the humidity measurement is made.

Temperature Units
The temperature units to use for all temperature parameters including sample temperature, dew-point, frost-point and wet bulb. e.g. °C

WMO Standard for %RH
Saturation vapour pressure is calculated over water even for temperatures below freezing as per WMO standard.

Rounding Weight
Total number of digits to show when rounding. Default 5.

Psychrometer Coefficient
Psychrometer coefficient for wet bulb calculations. Default 6.62 × 10^{-4}

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While every effort has been made to ensure the formulae used in this calculator are correct, this free software service is provided 'as-is' and without warranty or guarantee to the extent of the applicable law.