This European Standard establishes an evaluation procedure for determining equivalent conicity. A benchmark calculation is specified to achieve comparable results on a consistent basis for the equivalent conicity, which may be calculated by different methods not given in this European Standard. This European Standard also proposes possible calcualtion methods. Informative examples of the use of the Klingel formula (see Annex B) and linear regression of the Δr-function (see Annex C) are included in this European Standard.