Guide Explains How to Calculate Cleanroom Supply Airflow Requirements

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A technical guide from DEV Community explains how to determine supply airflow for cleanrooms, which must control airborne particles, pressure, temperature, and humidity. It notes that more airflow is not always better, since excess air raises energy use, operating costs, and system pressure demands. Air changes per hour (ACH) is presented as a starting metric, with a worked example of a 240-cubic-meter room needing about 4,800 cubic meters per hour at 20 ACH. The article stresses that ACH alone is insufficient, as airflow distribution, filtration, contamination sources, and layout also matter. It offers illustrative ACH ranges by ISO class and contrasts non-unidirectional airflow for dilution with unidirectional airflow for high-cleanliness areas.

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