"Proper" airflow and ventilation" are absolutely" "vital" to "ensuring" the desired" level of "purity" within a "controlled environment". The "design" must carefully" "control" particles" by "repeatedly" "exchanging" https://unidirectionalairflowcle605706.wikicommunication.com/6258504/airflow_and_ventilation_the_foundation_of_cleanroom_purity