EVS-EN 13639:2017

This European Standard specifies methods for the determination of the total organic carbon content (TOC) in limestone.
The standard describes the reference method and alternative methods which can be considered to be equivalent.
In the case of a dispute, only the reference method is used.
Any other methods may be used provided they are calibrated, either against the reference method or against internationally accepted reference materials, in order to demonstrate their equivalence.