All the dust filters I've seen advertised list their capabilities with
multi-micron-size dust particles. Irrelevant according to USCG
research. (Think overhauling ship engineering spaces.) Okay, they
reduce explosion hazard.

Gore-Tex filter in Shop-Vac alleges capability of removing 99+% of .3
micron particles. Over the years, I've been impressed at how they trap
extremely fine dust, like wood ash and drywall dust.

J