This document specifies two methods (method A and method B) of measuring the effect of the addition of any material claimed to have a liming effect on the soil, using the same basic principles. Method A measures the changes to the soil pH resulting from the addition of any material claimed to have a liming effect on a standard soil, measured over a period of one month. Method B assesses the efficiency of any material claimed to have a liming effect, using a range of defined soils and measured over a period of up to 2,5 years. The methods are not applicable to mineral products coarser than 6,3 mm for method A or 20 mm for method B, determined according to EN 12948. NOTE These methods allow comparison of products under controlled climatic conditions but do not replace field experiments.