Designing and Managing Airflow in a Cleanroom

Airflow in a cleanroom is one of the key components that you need to understand when designing a cleanroom. Airflow in a cleanroom is affected by many factors like the layout of the workflow in the room, ISO requirements the cleanroom needs to met as well as allowed size and structure the cleanroom will be in.

There are two basic types of airflow that need to be considered:

Turbulent Flow: This type of airflow is defined as air being pushed in to a cleanroom from an air handler device. You will often have several locations in the room where clean air will be blown in. This airflow tends to create a turbulence affect and cause particulates in the air to stay moving around until they can be passively pulled out through an air return path.

Laminar Flow: This type of airflow is typically pushed through the ceiling mounted filters or air outlets in to the room then returning through a raised access floor or side wall return air back to the main recirculating air handler units.

How a cleanroom will be used and what kinds of activities will take place in the room can determine which type of airflow will be the best to use.

Size and shape of your cleanroom will also affect airflow. The larger the room the more cost and energy used to keep the airflow working to an acceptable level.

In Ballroom cleanrooms raised access flooring systems or additional return air chases are needed throughout the cleanroom in order to achieve the Laminar airflow pattern.

Filters: Cleanroom filters come in various depths and efficiencies. Which filters to use depends mainly on the type of processes in the cleanroom and cleanroom

specifications. The correct type of filters must be considered as the pressure drop varies with each type of filters thus affecting the airflow.

Pressurization: Pressurization is another factor that needs to be considered early on during the design phase of the cleanroom. Depending upon the processes the cleanroom may need to have a positive pressure in relation to an adjacent room ( thus keeping particulates out of the the room) or it may be a negative pressure to prevent air from migrating in to an adjacent room such as in BSL Labs.

Designtek Consulting Group, with more than 40 years of experience in design and construction of cleanrooms, can help on your next cleanroom project in ensuring your success and allowing you to focus on your current business growth.