The inhabitants of cities, towns, and villages are exposed to different levels of air pollution, which also vary throughout the day. Information regarding episodes of poor and good air quality enables planning to mitigate the risks and maximize the benefits of spending time outdoors. In this work, an analysis was made of the state of air quality 2012–2016, using data gathered from automatic measuring stations located in five cities (> 50,000 inhabitants), five towns (5000–50,000 inhabitants), and five villages (< 5000 inhabitants) in five neighboring provinces in central Poland, in Central Europe. The monitoring stations were designated as “city background”, “town background”, and “rural background”. More than 3 million pieces of data were collected from 15 monitoring stations. This allowed the average daily changes in the concentration of air pollutants (NO 2 and NO x , O 3 , SO 2 , CO, PM 10 , PM 2.5 , C 6 H 6 ) to be determined, depending on the type of station and the size of the settlement unit in both winter periods and summer periods. As a result, the most and least favorable hours in terms of levels of air pollution were identified. This information could help to inform air quality management in modern cities, towns, and villages and to improve the quality of life, particularly among those most susceptible to the negative effects of air pollution, such as the elderly and children. Graphical Abstract

Wastewater treatment plants (WWTPs) generate considerable amounts of sewage sludge. The thermal sludge treatment system (TSTS) is therefore one of the most important technological units of a WWTP. However, due to technological processes involved in thermal sludge treatment, specific chemical, physical and biological conditions may arise that can affect air quality both within the WWTP area and in its vicinity. This study uses data from experimental measurements taken in and around a WWTP to assess the impact of thermal sludge treatment on air quality. The selected facility is located in the Group Sewage Treatment Plant in the Lodz Agglomeration and serves a population of around one million. The concentrations of harmful gaseous substances, bacteria, fungi, particulate matter and thermal energy were investigated. The qualitative and quantitative characteristics of physical, chemical, and biological factors and their influence on air quality are presented.

Thermal microclimate in a boiler room is formed by factors resulting from thermal processes that are taking place in combustion units. These factors are negatively affecting the indoor environment by worsening the air quality, and therefore it is crucial to maintain adequate air parameters in the room. It is a consequence of the fact that in the boiler room the operation of technological equipment results in an exposure of workers to adverse effects caused by thermal factors. Therefore, the evaluation of thermal conditions in the work area of people was made for the selected industrial boiler room using PMV and PPD indices (which allow to determine the thermal sensation of employees, regarding their surrounding thermal environment, based on the methodology of ISO 7730 standard). The analysis was based on own experimental measurements and numerical calculations made in the DesignBuilder program.

Abstract. The crucial impact on the indoor air quality in technological rooms, including boiler plant buildings, is made by operation of technological devices and ventilation systems. Therefore, the distribution of air temperature and velocity in these rooms mainly depends on location and heat gains generated by combustion devices, as well as emplacement of air supply and air exhaust elements. The temperature and airflow volume of supplied air is also an issue, because the indoor environment parameters are formed by the flow of air in the working area. Determination of the impact of physical factors on the thermal environment in a room is possible using an analysis of the air temperature and velocity. This issue is vital in terms of necessity to maintain the adequate heat conditions in the working area. Therefore, basing on the experimental measurements and numerical calculations (made in DesignBuilder software), the distribution of air temperature and velocity was analyzed in the selected industrial boiler room, located in the Lodz city, in Poland. The results obtained were compared with the recommended and limit values in the industrial buildings.

Concentration of air pollution in urbanized and agricultural areas is related to the activity of various economy sectors (the so-called SNAP categories). Therefore, the change in the emission of pollutants by an anthropogenic source should result in a change in the air pollution level in the selected area. To better understand the nature of changes in air pollution concentration in urban and agricultural areas, an analysis of data of five-year (2012-2016) air quality measurements, carried out at selected automatic air quality monitoring stations in Poland, Europe. The data came from stations located in 5 regions (Lower Silesia, Greater Poland, Lodz, Masovia and Lublin) in central Poland. The average hourly concentrations in selected areas in cities, towns and villages were compared with the hourly emission factors of power generation sector (SNAP1), residential and commercial combustion sector (SNAP2) and road transport sector (SNAP7). The hourly profiles of air pollution level were expressed by means of the “imission factor”, as analogous to the hourly profiles of the “emission factor” that is being used in the LOTOS-EUROS and the CHIMERE chemistry-transport models.