Assessment of ¹³⁷Cs contamination of combustion products and air pollution during the forest fires in zones of radioactive contamination

The results of the investigation of radiation hazard of forest fires in the radioactive contaminated areas in the article are presented. The activity concentration of long-lived radionuclides in forest fuel materials is shown. Airborne concentration of ¹³⁷Cs produced by the combustion of forest fuel materials with different contamination density can exceed the permissible activity levels of ¹³⁷Cs in air. During the large wildfires on the territories with high values of radioactive contamination density, the airborne concentration of radionuclides may be three or four times higher than the background values. Seasonal fluctuations of average volume activity were estimated by using the ratio between the values of aerosols activity in the atmosphere on the day of the fire (fire season) and the reference values. (authors)