"Adequate" airflow and ventilation" are absolutely" "essential" to "preserving" the "specified" level of "purity" within a "sterile area". The "design" must carefully" "control" particles" by "repeatedly" "filtering" https://whycleanroomventilationm633406.wizzardsblog.com/41789477/airflow-and-ventilation-the-foundation-of-cleanroom-purity