Clean Room Pressurizing and Evacuating

In clean room environments, maintaining the appropriate pressure is very important to control contamination. There are two different applications of clean room pressure manipulation: positive pressure clean room pressurizing and negative pressure clean room evacuating.

In positive pressure clean rooms, the objective is to keep foreign contaminants outside of the clean room. To do this, the clean room is constantly pressurized. A compressor or blower pushes filtered and compressed air into the room such that the air will tend towards the vents of the room to atmosphere, which is at lower pressure than the room. Immunocompromised patients are placed in positive pressure clean rooms to prevent exposure to airborne microorganisms, and these rooms are employed to prevent contamination in research applications as well. Positive pressure clean rooms are also used to prevent dust and dirt from entering manufacturing clean rooms where sensitive material, such as semiconductors or chemical products, are fabricated.

In negative pressure clean rooms, the objective is to keep any potentially hazardous suspended particulate matter within the clean room. In this case, a vacuum pump or blower will pull the air of the clean room, pushing it through filters out to atmosphere. Negative pressure clean rooms have been of enormous help in the recent COVID outbreaks, minimizing contamination of test equipment as well as reducing the spread of the pandemic. Negative pressure clean rooms continue to be of aid in similar situations where contagious maladies are contained.