ISO 14644-8:2013 establishes the classification of air chemical cleanliness (ACC) in cleanrooms and associated controlled environments, in terms of airborne concentrations of specific chemical substances (individual, group or category) and provides a protocol to include test methods, analysis and time-weighted factors within the specification for classification. ISO 14644-8:2013 currently considers only concentrations of air chemical contaminants between 100 and 10−12 g/m3 under cleanroom operational conditions. ISO 14644-8:2013 is not relevant for application in those industries, processes or productions where the presence of airborne chemical substances is not considered a risk to the product or process. It is not the intention of ISO 14644-8:2013 to describe the nature of air chemical contaminants. ISO 14644-8:2013 does not give a classification of surface chemical contamination.