This document specifies a method for the determination of the speed and effectiveness of the neutralizing potential of calcium carbonate, calcium magnesium carbonate and calcium magnesium silicate liming materials by potentiometric titration with hydrochloric acid. For liming materials coarser than 1 mm, it is essential to prepare the sample of a liming material by following exactly the description of Annex A. This method is applicable only to liming materials with a maximum particle size of 6,3 mm. The type of liming material can be identified according to EN 14069 and the particle size can be determined according to EN 12948.