This Technical Specification specifies a horizontal reference method for the determination of emissions of regulated dangerous substances from construction products into indoor air. This method is applicable to volatile organic compounds, semi-volatile organic compounds, and volatile aldehydes. It is based on the use of a test chamber and subsequent analysis of the organic compounds by GC-MS or HPLC. This Technical Specification is mainly aimed at determining the emission performance of construction products, when this is required under national provisions covered by the CPR (Regulation (EU) No. 305/2011).