A cleanroom is a working environment where concentration of airborne particles and contamination is controlled to maintain the specified limits. A cleanroom working environment is required at manufacturing units of semiconductors, pharmaceuticals, manufacturing centers, testing facilities and other critical environments where little contamination can be harmful.

Any contamination in a cleanroom generated by movement of people, manufacturing or research process and equipments should be removed or controlled up to the required standards. The Federal Standard 209E is widely followed cleanroom standard and guideline.