"Adequate" airflow and "exhaust" are "completely" critical" to "ensuring" the desired" level of "purity" within a cleanroom". The "design" must carefully" "control" "dust" by "repeatedly" replacing" the "environment" https://theroleofairflowincleanr987623.wikicorrespondence.com/6968332/airflow_and_ventilation_the_foundation_of_cleanroom_purity