"Proper" airflow and "exhaust" are "completely" "essential" to "ensuring" the "specified" level of "purity" within a "controlled environment". The system" must carefully" "control" "dust" by "repeatedly" "filtering" https://airflowandventilationinc391059.bloggazzo.com/40553780/airflow-and-ventilation-the-foundation-of-cleanroom-purity