Positive Pressure Clean Room Design

Effective positive and negative pressure rooms are an important part of industrial climate control systems.

Positive pressure clean room design.

In medical settings these rooms prevent the spread of infectious contaminants and maintain sterile or restricted spaces and are also referred to as protective environments positive pressure rooms and airborne infection isolation rooms aiir negative pressure rooms. Most homes have at least one negative pressure room. This is done by supplying more air and extracting less air from the room than is supplied to it. In a negative pressurised cleanroom the opposite occurs.

There are different cascading levels of positive air pressure from the cleanest rooms at the highest pressure down to the gown room or airlock room. The pressure must be greater in more stringent classified rooms so the air leaks towards the lesser clean rooms. Supplying airflow in sufficient volume and cleanliness to support the cleanliness rating of the room. The cleanroom is positively pressurized to 0 05 in wc with respect to the adjacent areas.

Positive pressure cleanrooms are used primarily for industries where the cleanroom functions to keep the product clean and safe from particulates like in the microelectronic industry where even the tiniest particle can damage the integrity of the microchips being manufactured. Positive pressure rooms also require 12 minimum airflow changes per hour and are required to maintain a minimum 0 01 in wc positive pressure differential ensuring that the patient is protected from airborne contamination. Maintaining a positive air space pressure in relation to adjoining dirtier cleanliness classification spaces is essential in preventing contaminants from infiltrating into a cleanroom. Positive air pressure means the cleanroom or rooms are pumped up with more filtered air then the surrounding space outside the cleanroom s.

The 4 important air conditioning design considerations for clean room system design are. It is very difficult to consistently maintain a space s cleanliness classification when it has neutral or negative space pressurization. The airflow must be greater in the adjacent room. Introducing air in a manner to prevent stagnant areas where particles could accumulate.

There is much more into the design of cleanrooms in terms of details of technology of. If the clean area pressure differential was positive to the corridor the powder would escape out of the room and enter the corridor and is likely then to be transferred into the next door cleanroom. A negative pressure room primarily keeps its air inside the room with controlled venting only. Whereas a positive pressure room keeps unfiltered air from outside the room out of the room all together.