Historical
BS EN ISO 14644-10:2013
Cleanrooms and associated controlled environments. Classification of surface cleanliness by chemical concentration (British Standard)
ISO 14644-10:2012 defines the classification system for cleanliness of surfaces in cleanrooms with regard to the presence of chemical compounds or elements (including molecules, ions, atoms and particles). It is applicable to all solid surfaces in cleanrooms and associated controlled environments such as walls, ceilings, floors, working environment, tools, equipment and devices.
British Standards Institution [bsi]