RE: How often should I test my cleanroom to ensure classification requirements?
Every 12 months air pressure difference and air flow testing should be conducted for all classifications of modular cleanrooms, as required by ISO. You should test the particle amounts in the room every year for ISO Class 6 and above cleanrooms. It is ok to do particle testing on cleanrooms class 5 and below every 6 months. Other tests include cleanroom filter testing, containment filter testing, recovery and airflow visualization. These tests are recommended at least every 2 years. To learn more about the cleanroom testing requirements, visit the ISO document 14644-2 Cleanroom Testing and Compliance.
The airborne-particle monitoring plan shall be based on risk assessment related to the application of the installation. The plan shall include, as a minimum, predetermined sample locations, minimum volume of air per sample, duration of measurements, number of measurements per sample location as required, time interval between measurements, particle size or sizes to be counted, and count acceptance limits, as well as count alert, action and excursion limits, if appropriate.
Excerpt from: ISO document 14644-2