This document specifies an instrumental method for the routine determination of pH within the range pH 2 to pH 12 using a glass electrode in a 1:5 (volume fraction) suspension of soil, sludge and treated biowaste in water (pH in H2O), in 1 mol/l potassium chloride solution (pH in KCl) or in 0,01 mol/l calcium chloride solution (pH in CaCl2). This International Standard is applicable to all types of soil, sludge and biowaste, for example pretreated in accordance with ISO 11464 or EN 16179.
