There are some car guys in Guangzhou tested car air filters with compressed air (in Chinese).
And their test shows that cleaning the filter with compressed air actually made it worse! Based on their data, you’d be better off using the dirty filter (and best off with a new filter, of course).
Smart Air did a test on vacuuming HEPA filter and it showed vacuuming improved performance by 10% on average, but the benefit is small and probably not worth the hassle. The only cleaning recommended is if there’s a lot of thick, easily removable debris on the filter, like leaves or cat hair. Otherwise, get a new filter!
Click here to read the original blog article: https://smartairfilters.com/en/blog/should-i-clean-wash-hepa-filter/