More information
Description
The municipality of Nižní Lhoty considers the measurement of air quality to be crucial. In the past, it has participated in the project for the acquisition of an AIS monitoring station. The station was eventually located in the municipality Nošovice. The village of Nižní Lhoty is located in the foothills of the Beskydy Mountains, however, it has a number of local issues. It is a typical village where heating with solid fuels is prevalent. Regular air monitoring will enable the municipality to strengthen its influence on citizens and to increase their awareness of their co-responsibility for air pollution. Ten locations will be monitored in area affected with local heating plants. Mixed zones with green heating can be used for comparison. All data will be sent to the MySQL data storage and further displayed as points, areas and graphs. The data will be exportable for further processing. Each measured site will have its own card (location, description, photos). The system will store other important sensor information, including validation factors determined at the beginning and during monitoring. The operation and quality of the measurements will be ensured by the project partner VŠB TU Ostrava.
Summary of project results
The project aimed to acquire, operate, and evaluate sensor measuring technology. Its primary objective was to verify the suitability of sensor technology for measuring air quality in municipalities, particularly concerning local heating. A fundamental issue is the growing popularity of sensor usage for measuring virtually anything, including air quality, without basic accountability for measurement quality. The market is literally inundated with sensors lacking laboratory validation. However, municipalities are part of public administration and require air quality measurements for their citizens. The results serve to implement measures such as boiler replacement, traffic optimization, or interventions in industry. Therefore, responsible measurement practices are essential. A database was prepared for further use by the Czech Hydrometeorological Institute (ČHMÚ) and for transferring experiences to other projects. The database is native, meaning it contains all events that occurred on the sensors, including failures, extremes, high or low sensitivity, etc. This is to understand proper selection and ensure responsible sensor operation. Additionally, the project found that municipalities are highly heterogeneous areas, and PMx air pollution is uneven. This could be due to local influences or sensor errors, which will need further monitoring in the data. However, the project brings further extensive experiences to appropriately adjust measurement quality. The measurements also demonstrated that sensors cannot replace reference measurements, which are far more robust and under constant control. Despite reservations, spatial data from sensors can be used for interpretation.
The sensors were acquired from a vendor through a public procurement process, and a fundamental condition for their acquisition was calibration before the commencement of measurements. Calibration was conducted at the Czech Hydrometeorological Institute (ČHMÚ), simultaneously for all sensors and the ENVEA reference dust monitor. The measurement period lasted for 40 days, culminating in the production of a validation protocol. Prior to the heating season, the selection of monitoring sites took place, totaling 15 across 3 areas of the municipality. The sensor placement was gradual, preceding the temperature drop and the actual start of the heating season. Validated sensors were continuously monitored by personnel, and the data were transmitted online to the Smartenvi.eu web server. The data file was transferred to ČHMÚ for further use in the agreed format, and the data are described in the project''s Final Report. The leadership of the involved municipalities utilized the results for regular citizen updates and anticipates further utilization in sustainability. A significant contribution to air protection is the established database, which can aid in future data auto-validation, sensor self-monitoring, and advanced interpretation. It is already evident that the sensors can be utilized to understand emissions/imissions dynamics in the municipality and can serve as a valuable tool in air quality protection. This need will grow with the pressure from the European Union to tighten limits from 2030 onwards.
The main output is a overseen database, which will further serve for setting up sensors as auxiliary measuring devices. The measurements also demonstrated that the advantage of sensors lies in their deployment in a network, where sensors correlate very well and their measurements are acceptably accurate. The problem remains with the correctness of the measured values compared to reference methods. The project results show that sensor measurements are indicative in relation to the limits and it is necessary to continuously monitor the sensors. At the same time, the situation in the area is very well described, namely whether there are any local sources of air pollution in the municipality - for example, the burning of poor quality fuels. An interesting fact is, for example, extreme air pollution at midnight during a fireworks display (NL26), which led to concentrations in the range of 10 000 micrograms, so it is questionable whether such activities should be phased out. These include burning grass and leaves or inconsistency in construction work. The city is very interested in measurement as an educational tool and for communication with citizens. Municipal management intends to invest in air protection measures in the future, if possible, and continuous measurement will help them selectively choose and control measures. Average PM10 concentrations in the heating season often exceed the annual limit of 40 µg/m³, with the worst affected areas being NL no. 12, no. 26, and no. 31, where average PM10 concentrations exceed 60 µg/m³. The maximum concentration was measured in the NL no. 26 area at 675 µg/m³. However, high concentrations were also recorded in other locations. Reference stations measure maximum concentrations lower, indicating that sensors tend to overestimate high values. Sensors correlate with each other in the range of 0.8 - 1.0, indicating that the network is consistent. Sensor measurement yield exceeds 90% in most cases
Air quality remains a fundamental issue for our citizens, which is why public administration focuses on its protection. The TOP_AIR Nižní Lhoty project aimed at continuous monitoring of suspended particles PM10 and PM2.5. Municipalities generally acknowledge the need to address dustiness, yet despite their knowledge of their territory, they struggle to identify the major culprits. In combination with the AIRP''S project (TROMSO), this monitoring is one of the outputs of Action Plans and supports sensible activities in the locality - from green care and road cleaning to transportation infrastructure and energy. Action plans serve as a repository of potential measures, but they require continuous monitoring. With the deadlines set by the EU in the Green Deal policy, the year 2030 is fast approaching, and significant changes in legislation concerning air protection are expected. If municipalities are not prepared, achieving changes that have a positive impact on health will be very challenging. Conversely, it is unfortunate that the entire public administration is not systematically addressed; problems can arise even in areas that currently appear to be in good condition. There are significant differences among sensors, although the correlation within the network is excellent, the alignment with the reference method is no longer straightforward. The degree of tightness ranges from minimal to significant, and this difference may be due to the location or the sensor itself. During the project implementation, validation checks were conducted, and subsequent changes to the validation factor were made; however, there were no significant changes in the measured PMx concentrations. Sensors exhibit a similar trend to reference measurements but vary in "sensitivity"; they also often have more significant deviations, i.e., randomly occurring outliers that would be advisable to eliminate from the results. The presented database is unaltered, due to the project''s goal of understanding sensor functionality correctly and defining how to use them.