National Physical Laboratory

Gas metrology software

Gas metrology software


GravCalc2 is Windows-based software that calculates the amount fraction and uncertainty of all components in gravimetrically prepared gas mixtures using the method described in ISO 6142. The program can be used for any gas mixture.

A copy of the program user guide can be downloaded free of charge here.

For further information about GravCalc2, or to request a quotation, please contact us.


XLGENLINE is MS Excel-based software that allows the user to perform generalised least squares (GLS) regression analysis that is fully compliant with ISO 6143. XLGENLINE calculates the amount fractions and estimated uncertainties of 'unknown' samples, displays a plot of the fitted regression function, and outputs the parameters of the fit (gradient, intercept, covariance, etc.).

The software, which can also be used for ordinary least squares (OLS) regression analysis can be downloaded free of charge from the Software Support for Metrology Downloads webpage.


Please email or telephone Customer Services on +44 20 8943 6151.

Last Updated: 16 Jun 2016
Created: 25 Sep 2013


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