Bests & Worsts Reviews from Amazon

I'm a respiratory therapist needing masks available at home for me and husband. This design had two things we were looking for: flexible nose band and chin cup for good seal. HERE'S THE PROBLEM - MERV ratings are for HVAC filters and not human face filters. Plus a MERV of 16 would allow something as small as corona19 through. Filtration for a human mask needs to be multi-layered and down to 0.3microns or less to be effective on a virus. And watch those prefixes; N95 and NK95 are approved NIOSH designations, nf is not a NIOSH approved rating for COVID19 or other aerosolized viral pathogens. It doesn't appear to be a proper prefix for anything