The DS3090 is a Danish standard for commissioning of installations in buildings. The standard describes the process of checking and documenting the installations during all phases of construction, from the initial ideas to the operational phase. The standard specifies which documents should be drawn up, which tests should be carried out and how the roles should be divided between the client, the commissioning manager, designers, contractors and suppliers. The standard is aimed at improving the quality of installations, minimising energy consumption and ensuring the safety and reliability of the building installations.