In the first half of October 2025, the average daily temperature dropped significantly, and the heating season began accordingly, which was also detected by the Green Sentinel’s air quality measuring instruments. The sudden increase in the amount of airborne dust is the result of solid fuel burning by the population: wood, coal, lignite, and in the worst cases, waste.

Decree No 6/2011 (I. 14.) VM on the rules for the assessment, monitoring and evaluation of air pollution levels and stationary air pollution sources sets out the requirements for the assessment methods of air pollution levels. An important factor in the assessment is the period of the year in which the air quality parameters are measured and assessed: the heating period is from 1 October of the year under consideration to 31 March of the year following the year under consideration; the non-heating period is from 1 April to 30 September of the year under consideration. During these two periods, particulate matter concentrations differ significantly, as is well confirmed by the Green Sentinel measurements.

The data from the evening hours of October 16, 2025, clearly illustrate the residential heating origin of the increase in airborne dust. Higher PM2.5 values were primarily observed at our measuring points in suburban areas within populated areas. Burning fuel in the evening hours results in more intense pollutant emissions during the initial combustion phase:

At monitoring stations in the city center, combustion products from residential heating accumulate due to the built-up nature of the area and its lower elevation:

Our station in Erdőspuszta, located at the Hármashegy forest school, serves as our reference point outside populated areas and clearly demonstrates that there are no emissions from residential heating in the surrounding area:

Individual responsibility is very important in reducing airborne dust, and we can do this both individually and collectively, primarily by using clean fuels (dry wood, pellets, gas), modern boilers, and well-maintained chimneys.

Further information on proper heating techniques is available from the Eco-Manager Office operating within the Green Areas Department of the Debrecen MJV Mayor's Office.

H-4024 Debrecen, Piac Street 20, Office No. 211.