Assoclima states that the most important national and international associations of experts in the air conditioning sector – including ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers), REHVA (Federation of European Heating, Ventilation and Air Conditioning associations) and AiCARR ( Italian Association of Air Conditioning, Heating, Refrigeration) – set up some working groups and elaborated documents and protocols on Covid 19.
The conclusion reached by the experts of the Associations is that the ventilation and filtration provided by the air conditioning systems used for winter heating and summer cooling contribute to reducing the concentration of SARS-CoV-2 in the air and therefore the risk of transmission. On the contrary, non-air conditioned spaces can cause thermal stress and, especially in the weaker subjects, reduce resistance to infections. In general, therefore, according to experts, turning off air conditioning and ventilation systems is not a recommended measure to reduce the transmission of the virus. All experts, including the Natiuonal Health Service and WHO, agree on the need for air exchange in rooms with external air intake or in a natural way, by opening the windows, or through air conditioning systems with mechanical ventilation.
As for the air conditioning systems, before they are switched on seasonally, it is necessary to proceed with the normal cleaning and maintenance activities aimed at ensuring their correct operation.
