Typically, air purifiers have two filters: A pre-filter and a main HEPA filter that does the heavy lifting. Depending on what’s going on inside and outside your home, those filters can get gunked up ...

Most air purifiers come with two different filters: a prefilter and a HEPA filter. Some even have a third filter. Each manufacturer's recommendations will vary in terms of cleaning the filters.

Keep in mind that less expensive vacuums can be sealed and have filters that grab 99% of particles down to 0.5 microns, but only a HEPA filter nabs 99.97% of particles as tiny as 0.3 microns (and ...

With a HEPA filter, washable metal filters and activated-carbon filters, this purifier can filter out 99.9 percent of particles 0.1 microns or larger from the air, according to Cuisinart, which ...

The best air purifiers feature true HEPA filters (not HEPA-grade or HEPA-like) that trap at least 99.97% of all particles with a diameter of 0.3 microns or larger.