UK Health & Safety Executive tested masks and concluded that N95 masks were the most effective. KN95 don't meet European standards though.
https://press.hse.gov.uk/2020/06/11/hse-safety-alert-issued-against-kn95-facemask/
UK Health & Safety Executive tested masks and concluded that N95 masks were the most effective. KN95 don't meet European standards though.
https://press.hse.gov.uk/2020/06/11/hse-safety-alert-issued-against-kn95-facemask/