ISO 16000-25 "Indoor air - Part 25: Determination of semi-volatile organic matter emissions in building products - Microchamber method" specifies a standard method for the determination of semi-volatile organic matter (SVOCs) emissions from building products using the microchamber method. This method involves the measurement of semi-vocs released into the air under specific conditions by testing samples of building materials in a small enclosed environment. The standard describes in detail the microchamber equipment, experimental conditions, sample prepatives and Measuring methods to ensure test accuracy and repeatability. This method is suitable for evaluating the impact of building materials and decorative products on indoor air mass, especially in the assessment of semi-volatile organic matter emissions, and provides a basis for formulating indoor air mass standards and relevant environmental regulations.