Some issues about ISO 14644-1: 2015 Classification of air cleanliness by particle concentration

 Classification of air cleanliness by particle concentration is the original source of ISO 14644 series standards of Cleanrooms and associated controlled environments. Since its publication, the standard has been widely recognized and adopted by the international scientific and technological experts. The domestic standards for cleanrooms and associated controlled environments are formulated directly and indirectly according to its basic principles. The domestic standards are currently being revised referring to the revised edition of ISO 14644 issued in recent years. Presents the method of determining the number of sampling locations and discusses the improper understandings of some issues in the revised edition of the standard.