“…Several other air purifying methods were also reported in the recent past. For example, ·OH Fog-drops based on an electric-field discharge plasma, which can kill microorganisms in air quickly [14] , [15] , [16] ; Ultra violet (UV) technology based of air sterilization [17] ; Air rapid heating rapid cooling sterilization [18] …etc. Useful information on such methods can be found in a review paper by Choi et al in 2021 [19] .…”