"Adequate" airflow and ventilation" are "fundamentally" "essential" to maintaining" the "required" level of "purity" within a "sterile area". The system" must "precisely" "regulate" "dust" by "repeatedly" "exchanging" https://why-cleanroom-ventilatio004874.wikijm.com/2396112/airflow_and_ventilation_the_foundation_of_cleanroom_purity