Pharmaceutical plants have complex production processes that place particularly high demands on cleanliness and sterility. There will be potential biological hazards in the production process, mainly the danger of infection, the toxicity, sensitization and other biological reactions of dead bacteria or dead cells and components or metabolism to the human body and other organisms, the toxicity, sensitization and other biological reactions of the product, and environmental effects. Therefore, pharmaceutical purification needs to control dust particles and microbial contamination in the pharmaceutical environment to prevent the introduction, generation and retention of pollutants in the area.