How often should a Sub-HEPA Filter be replaced?

There is no fixed replacement cycle for Sub-HEPA Filters. It needs to be determined based on the usage scenario, pollution level, and equipment condition to avoid premature replacement (wasting resources) or prolonged use that could affect filtration efficiency.
The basic replacement reference cycle is 6-12 months. For low-pollution scenarios such as ordinary offices and clean workshops, replacement every 10-12 months is recommended. For densely populated and dusty environments such as shopping malls and hospital clinics, it is suggested to shorten the cycle to 6-8 months. For heavily polluted environments such as chemical workshops and woodworking shops, inspection and replacement every 3-6 months are necessary, adjusted according to the actual pollution situation.
Key indicators require close monitoring. When the filter's operating resistance reaches twice its initial resistance, it must be replaced immediately; otherwise, ventilation efficiency will decrease and energy consumption will increase. Regularly inspect the filter surface; if significant dust accumulation, blackening, or a significant decrease in airflow occurs, replacement is necessary even if the reference cycle has not yet been reached.
A tip to extend lifespan: Using a pre-filter or medium-efficiency filter as a pre-treatment can reduce the contaminant load on the Sub-HEPA Filter. Regularly cleaning the area around the filter and keeping the ventilation system well-sealed can effectively extend the replacement cycle by preventing unfiltered air from entering directly.