The standards for Cleanroom cleanliness operate on a scale determined by the needs of specific industrial or research activities. Different levels of cleaning quality measure air suspension particle count where lower numbers relate to better cleanliness standards. The standards set by ISO 14644-1 and Chinese GMP specify complete guidelines regarding Cleanroom cleanliness levels. The classification of cleanroom environments consists of seven stages known as ISO 1 to ISO 9 whereas ISO 1 represents the highest level of cleanliness and ISO 9 represents the lowest.

Modern technology development has made semiconductor manufacturing essential for advancing electronics industry development. Cheapest and smallest particles encountered during the manufacturing stage have the power to damage both the functionality of chips and their manufacturing outcomes. Cleanrooms have now established themselves as critical components for every semiconductor production facility.

A Clean Room is a room in which the concentration of suspended particles in the air is controlled. It should be constructed and used to minimize the introduction, generation and retention of particles in the room. Other relevant parameters such as temperature, humidity, pressure, etc. are required to be controlled. Air cleanliness refers to the extent of the amount of dust particles in the air in a clean environment, high dust concentration is low cleanliness, low dust concentration is high cleanliness.

Class C bioengineering Cleanroom is a clean level in the field of bioengineering based on air cleanliness, air pressure, air volume, temperature and humidity, noise, microbial content and other indicators. It is mainly used for clean operation areas of lower importance in the process of producing sterile drugs, such as the preliminary processing of cell culture, genetic testing and other links.