This document specifies a method for measuring the pH value of bituminous emulsions. It is applicable to anionic, cationic bituminous emulsions and bituminous emulsions prepared by means of non-ionic surfactant. In certain circumstances, the pH value can provide an indication of the ionic character of a bituminous emulsion. However, this indication should be confirmed by a particle polarity test conforming to EN 1430 [1]. WARNING The use of this document can involve hazardous materials, operations and equipment. This document does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this document to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.