Related health international organization there are two principal way of transmission of coronavirus covid- 19: direct contact whit infected subject or by droplets. Other way under deep investigation by researcher is airborne transmission. Related the evidence presented in this work is possible to verify that in indoor settings this is possible. Relevant is the distance considered. Observing the role played by PM10 of polluted air in accelerated diffusion of covid-19 in some world region Is interesting to observe the effect of musk use to reduce intake of this pollutants for a significative period. All this evidence must be applied in many healthcare settings like oncology or towards immunodepressed (or other kind of vulnerable condition) patients also during access to hospitals. ICU settings are the hospital area subjected to severe procedure to prevent diffusion of Covid -19 and other infectious disease like MDR bacteria or some invasive fungal but according published evidences other area in hospital settings must be considered at risk to diffuse this kind of infectious disease.