What is the particle limit for ISO Class 7 according to the classifications?

ISO Class 7 is part of the ISO 14644-1 classification system, which categorizes cleanrooms based on the maximum allowable levels of airborne particulate contamination. For ISO Class 7, the standard specifies a limit of fewer than 10,000 particles per cubic foot (ft³) of air that are 0.5 micrometers or larger. This classification is critical in environments where maintaining a certain level of cleanliness is essential, such as in pharmaceutical manufacturing, sterile compounding, and other settings that require control over the particulate load in the air.

This limit ensures that the environment is kept sufficiently clean to prevent contamination during the handling or processing of sensitive materials. While other classes in the ISO system have different particle thresholds, Class 7 is specifically defined by the 10,000 particles/ft³ limit, making it a key benchmark in cleanroom specifications.