Fig. 2 Electric heater designed to inactivate airborne SARS-CoV-2 at high temperatures as air passes through it. The electric heater consists of a fan and stainless steel electric tube heating elements. The electric heater’s fan draws outside air into the heater. The air heat energy increases by interacting with stainless steel electric tube heating elements perpendicularly to the airflow direction.
Two electric heaters were used to inactivate the airborne virus in the 30 m3 test room. The small electric heater had a power of 1.5 kW, an airflow rate of 44 m3/hour, an air travel time through the air tunnel of 0.97 seconds, and an outlet air temperature of 220 oC. The large electric heater had a power of 3 kW, an airflow rate of 324 m3/h, an air travel time through the air tunnel of 0.03 seconds, and an outlet air temperature of 150 oC. Air travel time through the tunnel was measured as described elsewhere (Canpolat et al., 2022).