Q：If air change frequency for Class 100,000 clean room is 15~25 times/hour, is 15 times/hour or 25 times/hour proper in the desi
Whether minimum or maximum is taken for air change frequency, following factors should be considered:
Is HEPA mounted on AHU or air outlet?
Efficiency of primary and intermediary strainers
Efficiency and number of HEPA
Indoor dust loading condition
Situation of access management
Quality of air duct
Generally, median is taken is the design, however, if HEPA is mounted upstream air duct (i.e. AHU outlet), maximum is recommended.