A cleanroom is a room in which the concentration of airborne particles is kept with in the specified limit and it is constructed in a manner to minimize the introduction, generation, and retention of particles in the room and other relevant parameters, example temperature, humidity and pressure are controlled as necessary.

The integrity of the cleanroom environment is created by the pressure differential   compared with adjacent areas through heating, ventilation and air-conditioning system.

Supplying airflow in sufficient volume to support the cleanliness rating of the room.

Introducing air in a manner to prevent stagnant areas where particles could accumulate.

Filtering the outside and re-circulated air across high efficiency particulate air (HEPA) filters.

Conditioning the air to meet the cleanroom temperature and humidity requirements.

Ensuring enough conditioned makeup air to maintain the specified positive pressurization.