Mask disinfection using atmospheric pressure cold plasma

•KN95 and filtering face piece two masks were disinfected by atmospheric pressure cold plasma.•Nitrogen plasma treatment achieved the best bacterial inactivation.•Pseudomonas aeruginosa and Escherichia coli were inactivated mainly by the thermal effect.•Reactive oxygen and nitrogen species generated in plasma were the main cause of the Staphylococcus aureus antimicrobial effect.•Filtration capacity and breathability did not change after five cycles of plasma treatment.