In the first generation of harmonised standards and approval guidelines in accordance with the framework of the construction products directive, no requirements were included for the fulfilment of Essential requirement no. 3 Hygiene, Health and Environment. These requirements shall be included in the revision of the standards, i.e., in the second generation. For this purpose, the European Commission has provided Mandate M/366 Horizontal Complement to Mandates CEN/CENELEC, Concerning the Execution of Standardisation Work for the Development of Horizontal Standardised Assessment Methods for Harmonised Approaches Relating to Dangerous Substances Under the Construction Products Directive (CPD).