Question: are dyson air purifiers any good?
Answer: Dyson Pure Cool Review - Filtration Dyson has said that the Pure Cool can remove 99.95% as small as 0.1 microns of allergens from the air. Due to the way the air comes out of the unit, we were not able to verify that number and measured a filtration efficiency that was closer to 90% at 0.3 micron.