12. EMISSIONS OF SULPHUR DIOXIDE

Transcription

1 Air Air quality is to a great extent influenced by combustion of fossil fuels, evaporation of volatile organic compounds and their photochemical reaction with other pollutants in the atmosphere. Pollutants may be of either biogenic (emissions from forest, sea, active volcanoes, etc.) or anthropogenic (industry, transport, thermal power plants, etc.) origin. Part of air pollution also results from long-range transboundary transport of pollutants, which especially applies to ozone and particulate matter. Despite the reduction in pollutant emissions, air pollution still has adverse effects on human health and ecosystems, and causes damage to materials. The largest share of emissions is attributed to the combustion in energy production and transport sector, which is also clearly evident from the Preliminary assessment of the ambient air quality in Slovenia, made in 23. The assessment shows that air quality in Slovenia is predominantly influenced by pollution with sulphur dioxide, nitrogen oxides and particulate matter (PM1). Great consideration should also be given to the problem of air pollution with ground-level ozone, which differs from other air pollutants particularly with regard to the chemical process of its production. That is, ground-level ozone does not emit but results directly from photochemical reactions occurring in the interaction with other pollutants in the atmosphere. Also problematic is a long-range transbounary transport of ozone, especially from Italy. Air quality indicators presented in this report include pressures (emissions) and state of air pollution (air quality). The emissions-related indicators deal mainly with quantitative illustration, sector-specific distribution and pollution trends. The data on air quality are acquired from the ambient air pollution measurement network, maintained by the Environmental Agency of the Republic of Slovenia. They indicate to the number of limit value exceedances for pollutants that have been confirmed as problematic in the preliminary assessment (i.e. sulphur dioxide, nitrogen oxides, particulate matter PM1)

2 12. EMISSIONS OF SULPHUR DIOXIDE driving forces pressures responses state impacts The indicator shows the trend in quantities of total sulphur dioxide (SO 2 ) emissions in Slovenia and main source categories. The quantities of emissions are calculated in accordance with the methodology for creating the National Emission Inventory, based on the CORIN methodology. The emissions are shown in a time series from 199 to 22. GOAL The target is to reduce SO 2 emissions to the target value 27, as required by the Protocol on the Reduction of Acidification, Eutrophication and Ground Ozone, and Directive 21/81/EC on National Emissions Ceilings for Certain Atmospheric Pollutants (NECD). Air emission management and reduction is also a target of the National Environmental Action Programme. Figure 12-1: Annual SO 2 emissions in Slovenia and the target value for S 2 emissions (index 199=1) emissions SO 2 target trend target value Figure 12-2: Sector-specific contribution to total SO 2 emissions in Slovenia in 22 8% 4% 6% 1% 81% combustion in energy production technological processes transport combustion in industry non-industrial combustion 42

3 SO 2 emissions in Slovenia have dropped by 64 % compared to the value in 199. This reduction may be ascribed to the start-up of the desulphurisation unit on block 4 of the Šoštanj power plant as well as to the introduction of natural gas and liquid fuels with lower sulphur content. DATA AND SOURCES Table 12-1: Annual SO 2 emissions in Slovenia and the target value for 21 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit target 21 SO 2 emissions 1 t SO 2 emissions index (199 = 1) Table 12-2: Sector-specific contribution to total SO 2 emissions in Slovenia in 22 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit combustion in energy production combustion in industry technological processes non-industrial combustion transport SO 2 emissions 1 t share of sectors % total The data are taken from the National Emission Inventory database. The database maintained at the Environmental Agency of the Republic of Slovenia contains emission assessments that are made on the basis of statistical data (on sold fuels, industrial production, agricultural activities, etc.) by using emission factors. 43

4 13. EMISSIONS OF NITROGEN OXIDES driving forces pressures responses state impacts The indicator shows the trend in quantities of total nitrogen oxide (NO x ) emissions in Slovenia and main source categories. The quantities of emissions are calculated in accordance with the methodology for creating the National Emission Inventory, based on the CORIN methodology. The emissions are shown in a time series from 199 to 22. GOAL The target is to reduce NO x emissions to the target value 45, as required by the Protocol on the Reduction of Acidification, Eutrophication and Ground Ozone, and Directive 21/81/EC on National Emissions Ceilings for Certain Atmospheric Pollutants (NECD). Air emission management and reduction is also a target of the National Environmental Action Programme. Figure 13-1: Annual NO x emissions in Slovenia and the target value set for NO x emissions (index 199=1) NO x emissions target trend target value Figure 13-2: Sector-specific contribution to total NO x emissions in Slovenia in 22 58% 1% 3% energy combustion in industry non-industrial combustion road transport other transport 5% 6% 44

5 Compared to the situation in 199, NO x emissions in Slovenia dropped by 9 % in 22. This reduction is the result of an increased portion of vehicles with catalytic converters. With the 58% share of NO x emissions, road traffic remains the principal source of pollution. DATA AND SOURCES Table 13-1: Annual NO x emissions in Slovenia and the target value set for 21 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit target 21 NO x emissions 1 t NO x emissions index (199 = 1) Table 13-2: Sector-specific contribution to total NO x emissions in Slovenia in 22 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit energy combustion in industry non-industrial combustion road transport other transport total NO x emissions 1 t share of sectors % The data are taken from the National Emission Inventory database. The database maintained at the Environmental Agency of the Republic of Slovenia contains emission assessments that are made on the basis of statistical data (on sold fuels, industrial production, agricultural activities, etc.) by using emission factors. 45

6 14. EMISSIONS OF AMMONIA driving forces pressures responses state impacts The indicator shows the trend in quantities of total ammonia (NH 3 ) emissions in Slovenia. The quantities of emissions are calculated in accordance with the methodology for creating the National Emission Inventory, based on the CORIN methodology. The emissions are shown in a time series from 199 to 22. GOAL Reduction in NH 3 emissions to the target value 2 is required by the Protocol on the Reduction of Acidification, Eutrophication and Ground Ozone, and Directive 21/81/EC on National Emissions Ceilings for Certain Atmospheric Pollutants (NECD). Air emission management and reduction is also a target of the National Environmental Action Programme. Figure 14-1: Annual NH 3 emissions in Slovenia and the target value set for NH3 emissions (index 199=1) 21 NH3 emissions target trend target value Most NH 3 emissions are from agricultural production. Between 199 and 22, NH 3 emissions dropped by 2 %. This reduction may be attributed to the decrease in the number of livestock units. In 22, NH 3 emissions were 3 % lower than the envisaged target path leading to the target emission value for Slovenia (2 ). DATA AND SOURCES The data are taken from the National Emission Inventory database. The database maintained at the Environmental Agency of the Republic of Slovenia contains emission assessments that are made on the basis of statistical data (on sold fuels, industrial production, agricultural activities, etc.) by using emission factors. Table 14-1: Annual NH 3 emissions in Slovenia and the target value set for 21 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit cilj 21 NH 3 emissions 1 t NH 3 emissions index (199 = 1)

7 driving forces pressures responses state impacts 15. EMISSIONS OF NON-METHANE VOLATILE ORGANIC COMPOUNDS The indicator shows the trend in quantities of total non-methane volatile organic compounds (NMVOC) emissions in Slovenia and main source categories. The quantities of emissions are calculated in accordance with the methodology for creating the National Emission Inventory, based on the CORIN methodology. The emissions are shown in a time series from 199 to 22. GOAL The main purpose of this indicator is to show NMVOC emissions and reduction thereof to the target value 4, as required by the Protocol on the Reduction of Acidification, Eutrophication and Ground Ozone, and Directive 21/81/EC on National Emissions Ceilings for Certain Atmospheric Pollutants (NECD). Air emission management and reduction is also a target of the National Environmental Action Programme. Figure 15-1: Annual NMVOC emissions in Slovenia and the target value set for NMVOC emissions (index 199=1) target trend target value NMVOC emissions Figure 15-2: Sector-specific contributions to NMVOC emissions in Slovenia in 22 3,8%,1% 3,6 % 11,1 % 2,7% 9,3% 19,3% energy fugitive emissions combustion in industry technological process non-industrial combustion use of solvents road transport other transport 23,% 47

8 NMVOC emissions in Slovenia have dropped by 12% compared to the value in 199. This reduction is the result of an increased portion of vehicles with catalytic converters. NMVOC emissions in 22 are 4 % lower than the envisaged target path leading to the target value for Slovenia (4 ). DATA AND SOURCES Table 15-1: Annual NMVOC emissions in Slovenia and the target value set for 21 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit target 21 NMVOCs emissions 1 t NMVOCs emissions index (199=1) Table 15-2: Sector-specific contributions to NMVOC emissions in Slovenia in 22 Source: National Emission Inventory, Environmental Agency of the Republic of Slovenia, 24 unit energy fugitive emissions combustion in industry technological process non-industrial combustion use of solvents road transport other transport NMVOCs emissions 1 t share of sectors % The data are taken from the National Emission Inventory database. The database maintained at the Environmental Agency of the Republic of Slovenia contains emission assessments that are made on the basis of statistical data (on sold fuels, industrial production, agricultural activities, etc.) by using emission factors. 48

9 driving forces pressures responses impacts state 16. POLLUTION WITH SULPHUR DIOXIDE The main sources of sulphur dioxide (SO 2 ) emissions are large thermal power plants and heat production plants, and in urban areas also small and medium-sized coal-burning boiler facilities. SO 2 is also produced in certain processes in industry (e.g. cellulose production plants). The indicator shows the frequency in exceedances of 1-hour limit concentration value (35 µg/m 3 ) and the frequency in exceedances of 24-hour limit concentration value (125 µg/m 3 ) for SO 2 in the most polluted Slovenian urban areas by individual year. GOAL The main aim of air quality management is reduction of air pollution in Slovenia caused by SO 2, as stated in the Decree on Sulphur Dioxide, Nitrogen Oxides, Particulate Matter and Lead in Ambient Air (OJ RS No 52/2) and the EU Directive (1999/3/EC). Legislation provides that average 24-hour concentration of SO 2 may exceed the value 125 µg/m 3 not more than three times per calendar year, and average 1-hour concentration of SO 2 may exceed the permissible 1-hour value not more than 24 times per calendar year. Since, according to the Decree, the permissible 1-hour value will reach the target limit value 35 µg/m 3 in 25, the indicator also shows the exceedances of this target limit value for the purposes of comparison with the preceding years. The target is to ensure that the requirements of this Decree are fulfilled. Reduction of air pollution due to SO 2 is also a target of the National Environmental Action Programme. Figure 16-1: Number of hours with SO 2 concentrations exceeding average 1-hour limit value - 35 µg/m 3 in Slovenian urban areas 4 numbers of hours with exceedances Ljubljana Maribor Celje Trbovlje Zagorje Hrastnik Velenje Šoštanj Topolšica permitted exceedances 49

10 Figure 16-2: Number of days with SO 2 concentrations exceeding average 24-hour limit value µg/m3 in Slovenian urban areas 7 number of days with exceedances Ljubljana Maribor Celje Trbovlje Zagorje Hrastnik Velenje Šoštanj Topolšica permitted exceedances The figures clearly demonstrate that Slovenia has in some urban areas achieved the required standards. The exception is Šoštanj, where the monitoring site is influenced by emissions from the thermal power plant, and the established hourly and daily limit values have been exceeded too frequently. There are also occasional exceedances of limit values in the Zasavje urban areas, which have an unfavourable geographical position and are, in addition to local emission sources, also affected by the influence of emissions from the Trbovlje Thermal Power Plant. The Šoštanj problem is being resolved with desulphurisation units having been installed and put into operation on blocks 4 and 5. The rehabilitation programme, furthermore, envisages that the operating desulphurisation system will also incorporate blocks 1, 2 and 3; the necessary works are already under way. The two discussed indicators show a downward trend in other EU countries as well. 5

11 DATA AND SOURCES Table 16-1: Number of hours with SO2 concentrations exceeding average 1-hour limit value - 35 µg/m3 in Slovenian urban areas Source: Automatic air quality measurement database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana number of hours Maribor number of hours 41 7 Celje number of hours Trbovlje number of hours Zagorje number of hours Hrastnik number of hours Velenje number of hours Šoštanj number of hours Topolšica number of hours Table 16-2: Number of days with SO 2 concentrations exceeding average 24-hour limit value µg/m 3 in Slovenian urban areas Source: Automatic air quality measurement database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana number of days Maribor number of days Celje number of days Trbovlje number of days Zagorje number of days Hrastnik number of days Velenje number of days Šoštanj number of days Topolšica number of days The data for Slovenia are taken from the Automatic air quality measurement database (ANAS) maintained by the Monitoring Office (Environmental Agency of the Republic of Slovenia) and Šoštanj Thermal Power Plant measurement database provided by the Electroinstitute Milan Vidmar, Ljubljana. The database is updated monthly; the data are available in their entirety upon the completion of final annual review. Information on the ANAS automatic network monitoring sites: Ljubljana has two monitoring sites Figovec and Bežigrad. Last measurements at Figovec monitoring site were made in 21. By the end of that same year, it was put out of operation, since the Bežigrad monitoring site was considered representative enough for determining the impact on health of the majority of Ljubljana s population. The monitoring site in Maribor is located directly at the carriageway in the city centre, near an intersection; therefore the air samples show a higher level of traffic-related pollution. Since traffic is not the source of SO 2, the monitoring site is also representative for a wider urban area. In Celje, measurements are taken in the hospital complex located just outside the city centre. The monitoring site is representative for a wider urban area. The Trbovlje and Zagorje monitoring sites are set up at roadside locations in the city centres. The Hrastnik monitoring site, however, is not directly affected by the influence of traffic-related emissions. All three monitoring sites are representative of the above mentioned urban areas. Information on the Šoštanj Thermal Power Plant automatic network monitoring sites: The Šoštanj monitoring site is located east of the city and in the event of south-western winds is exposed to the influence of emissions from lower stacks of the Šoštanj Thermal Power Plant. The measured SO 2, concentrations are not representative for the Šoštanj urban area. The monitoring site at Topolšica is representative for the Topolšica urban area. The Velenje monitoring site is representative of the city of Velenje. 51

12 17. POLLUTION WITH NITROGEN OXIDES driving forces pressures responses impacts state Nitrogen oxides (NO x ) play an important role in air pollution phenomena such as acidification, eutrophication and photochemical smog. The main source of NO x within urban areas is traffic. Otherwise, nitrogen dioxide (NO 2 ) concentrations are also determined by meteorological conditions. The amount of NO x is crucially influenced by ozone. The indicator shows the frequency of exceeding the 1-hour limit concentration values of NO 2 exceeding 2 µg/m 3 and average annual NO 2 concentrations (limit annual value is 4 µg/m 3 ). GOAL The main aim of air quality management is reduction of air pollution in Slovenia caused by NO 2, as stated in the Decree on Sulphur Dioxide, Nitrogen oxides, Particulate Matter and Lead in Ambient Air (OJ RS, No 52/2) and the EU Directive (1999/3/EC). Legislation provides that average 1-hour concentration of NO 2 may not exceed the limit value of 2 µg/m 3 more than 18 times per calendar year. Annual NO 2 concentration, however, may not exceed 4 µg/m 3. Air emission management and pollution reduction is also a target of the National Environmental Action Programme. Figure 17-1: Number of hours with exceeded average 1-hour limit value of NO 2 concentration 2 µg/m 3 in Slovenian urban areas 25 number of hour with exceedances 2 Ljubljana Figovec 15 Maribor Celje 1 Trbovlje 5 permitted exceedances Figure 17-2: Average annual concentration of NO 2 (annual limit value is 4 µg/m 3 ) 6 5 concentration (µg/m 3 ) Maribor Celje Trbovlje Ljubljana Figovec annual limit value 52

13 The introduction of EU legislation has resulted in the reduction of NO X emissions. The highest NO 2 concentrations are found at roadside locations. The use of catalytic converters in vehicles led to a significant reduction in emissions. Figure 17-1 clearly shows that in urban areas Slovenia has already achieved the required standards relating to exceedances of 1-hour limit values at individual monitoring sites, since in 21 and 22 there was none recorded. Average annual values of NO 2 (Figure 17-2), as well, have been maintained below the limit value and individual monitoring sites show a slight downward trend. Analyses of NO 2 concentration measurements in other European countries indicate a slightly downward trend in annual value since Monitoring sites in urban areas show that annual limit values are more often exceeded than 1-hour limit values. DATA AND SOURCES Table 17-1: Number of hours with exceeded average 1-hour limit value of NO 2 concentration 2 µg/m 3 in Slovenian urban areas Source: Automatic Air Quality Measurement Database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana Figovec number of hours Maribor number of hours Celje number of hours n/a Trbovlje number of hours n/a n/a n/a n/a n/a Table 17-2: Average annual concentration of NO 2 (annual limit value is 4 µg/m 3 ) Source: Automatic Air Quality Measurement Database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana Figovec µg/m n/a Maribor µg/m Celje µg/m n/a Trbovlje µg/m 3 n/a n/a n/a n/a n/a n/a 28 The data for Slovenia are taken from the Automatic air quality measurement database (ANAS) maintained at the Monitoring Office (Environmental Agency of the Republic of Slovenia). The database is updated monthly; the data are available in their entirety upon the completion of final annual review. 53

14 18. POLLUTION WITH OZONE driving forces pressures responses impacts state The indicator shows the frequencies in the exceeding the target ozone value and the ozone alert threshold per calendar year. The target value for 21 is set according to the World Health Organisation guidelines for Europe (Fact Sheet No 187, WHO s 1999 Guidelines for Air Pollution Control). It is determined in such a way that the highest average 8-hour running value is calculated from 1-hour concentrations for each day. The highest 8-hour concentration of ozone may not exceed 12 µg/m 3 for more than 25 days per year (calculated as a three-year average). The alert threshold is defined as 1-hour concentration higher than 18 µg/m 3. This value, as well, is set according to the World Health Organisation guidelines for Europe. It is intended for the protection of human health from short-term exposure to high concentrations of ozone. With such a high level of concentration there is a need to start warning the population of excessive ozone concentrations. The alert value is set at 24 µg/m 3 ; however, during the last decade it has rarely been reached in Slovenia. GOAL In accordance with the Decree on Ozone in Ambient Air (OJ RS, No 8/3) containing the provisions from Directive 22/3/EC, our objective is that by 21, no monitoring site will indicate exceedance of both target and alert threshold values. These values are determined with a view to protect human health from long-term exposure to high ozone concentrations. Figure 18-1: Number of days with exceeded target value for ozone in Slovenian urban areas (highest average 8-hour floating value > 12 µg/m 3 ) 6 number of days with exceedances Ljubljana Maribor Celje Velenje Nova Gorica Trbovlje Hrastnik 54

15 Figure 18-2: Number of days with exceeded target value for ozone in Slovenian urban areas (highest 1-hour value > 18 µg/m 3 ) number of days with exceedances Ljubljana Celje Velenje Nova Gorica Hrastnik Being a product of photochemical reactions, tropospheric ozone differs from certain other pollutants. Its precursors, especially nitrogen oxides, are substances forming ozone through the above mentioned photochemical reactions. In Slovenia, transport is regarded to be the greatest source of ozone. Ozone concentrations exhibit an explicit annual curve which is strongly connected with ozone formation requiring an adequate amount of sunlight. Another crucial contributor to the ozone formation is a long-range (transboundary) transport as the Po Valley in Italy is one of the areas in Europe producing the greatest amounts of ozone. The data do not display a clear trend. Levels of ozone concentrations are determined by emissions of ozone precursors as well as spring and summer weather conditions, and are subject to change year on year. In 21, a renewed and extended air quality measurement network was put into operation, enabling a trend assessment that will be made on the basis of a larger and higher quality suite of data. Slovenia is divided into areas by different levels of air-pollution threat. With regard to ozone, all areas fall within the lowest quality class, as the ozone concentrations exceed the target values throughout the country, including its rural and mountainous areas. The most polluted area in Slovenia is the Primorska region due to ozone transport from the Po Valley. 55

16 DATA AND SOURCES Table 18-1: Number of days with exceeded target value for ozone in Slovenian urban areas (highest average 8-hour floating value > 12 µg/m 3 ) Source: Automatic Air Quality Measurement Database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana number of days Maribor number of days n/a n/a Celje number of days n/a n/a Velenje number of days n/a n/a Nova Gorica number of days n/a n/a n/a n/a n/a n/a n/a 36 Trbovlje number of days n/a n/a n/a n/a 9 Hrastnik number of days n/a n/a Table 18-2: Number of days with exceeded target value for ozone in Slovenian urban areas (highest 1-hour value > 18 µg/m 3 ) Source: Automatic Air Quality Measurement Database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana number of days Maribor number of days n/a n/a Celje number of days n/a n/a 1 3 Velenje number of days n/a n/a 1 1 Nova Gorica number of days n/a n/a n/a n/a n/a n/a n/a 26 Trbovlje number of days n/a n/a n/a n/a Hrastnik number of days n/a n/a 2 2 With the exception of the monitoring site in Velenje, which is part of information system managed by the TE Šoštanj, all the data are taken from the Automatic air quality measurement database (ANAS) maintained by the Monitoring Office (Environmental Agency of the Republic of Slovenia). The data from individual monitoring sites are not directly comparable due to different types of locations with regard to the influence of pollution sources. The Ljubljana, Celje, Velenje and Nova Gorica monitoring sites are not directly affected by the influence of traffic-related emissions. The Maribor and Trbovlje monitoring sites are placed at roadside locations, where ozone reacts with nitrogen oxides from exhaust gases, thus causing the indices of ozone concentrations to be appreciably lower. The monitoring site in Hrastnik is located at the verge of the urban area; in the event of south-western winds it is exposed to the influence of flue gases from the Trbovlje Thermal Power Plant, which may also have a lowering effect on ozone concentrations. Although provided by a smaller number of monitoring sites, the data on ozone concentrations have otherwise been available since The number of monitoring sites increased in 22. In order to illustrate the trend, the exceedances of target and alert threshold values are also shown for previous years, according to the current Decree on ozone in ambient air, since the limit values as determined in formerly applicable regulations are not comparable with the present target and alert threshold values. 56

17 driving forces pressures responses impacts state 19. POLLUTION WITH PARTICULATE MATTER The indicator shows the number of days per year when the 24- hour limit concentration 5 µg/m 3 and the annual limit value 4 µg/m 3 were exceeded in the selected Slovenian urban areas that are most affected by pollution. Particulate matter means a combination of finely divided solid or liquid particles suspended in the air, of various physical and chemical compositions. A portion of airborne particles is formed as a consequence of direct emissions (primary particles), others are formed as products of various processes in the atmosphere (secondary particles). Particle size distribution is usually described in terms of trimodal size distribution. Particles ranging between.1 and.1 µm belong in the so-called nucleation area, particles ranging between.1 and 1 µm belong in the accumulation area, and particles larger than 1 µm are known as coarse particles. GOAL The Decree on Sulphur Dioxide, Nitrogen Oxides, Particulate Matter and Lead in Ambient Air (OJ RS No 52/2) and EU Directive (1999/3/EC), determine the 24-hour limit concentration value at 5 µg/m 3 not to be exceeded more than 35 times per calendar year, and annual limit value at 4 µg/m 3. Figure 19-1: Number of days with exceeded 24-hour limit concentration PM1 5 µg/m 3, which may not be exceeded more than 35 times per calendar year 14 Ljubljana Bežigrad 12 Maribor number of days with exceedances Celje Murska Sobota Rakičan Nova Gorica Trbovlje Zagorje Ljubljana Figovec permited exceedances Figure 19-2: Average annual concentration (annual limit value is 4 µg/m 3 ) 6 5 concentration (µg/m3) Ljubljana Bežigrad Maribor Celje Murska Sobota Rakičan Nova Gorica Trbovlje Zagorje Ljubljana Figovec annual limit value 57

18 Measurements of particlulate matter (PM1) concentration levels in several urban areas came into practice with the introduction of a new air quality monitoring network (i.e. PHARE monitoring network) in March 21. As is clearly evident from Figure 19-1, particulate matter poses a serious problem not only in Slovenian urban areas but also throughout Europe. In 22, 24-hour limit values were exceeded more than 35 times per calendar year at five monitoring sites. Since the latter are mainly placed in heavy traffic locations, emissions from traffic bear a significant influence on particulate matter concentration levels in ambient air. DATA AND SOURCES Table 19-1: Number of days with exceeded 24-hour limit concentration PM1 5 µg/m 3, which may not be exceeded more than 35 times per calendar year Source: Automatic Air Quality Measurement Database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana Figovec number of days n/a Ljubljana Bežigrad number of days n/a n/a n/a n/a 47 Maribor number of days n/a n/a n/a n/a 81 Celje number of days Murska Sobota-Rakičan number of days n/a n/a n/a n/a 38 Nova Gorica number of days n/a n/a n/a n/a 31 Trbovlje number of days Zagorje number of days n/a n/a n/a n/a 64 Table 19-2: Average annual concentration (annual limit value is 4 µg/m3) Source: Automatic Air Quality Measurement Database (ANAS), Environmental Agency of the Republic of Slovenia, 23 monitoring site unit Ljubljana Figovec µg/m n/a Ljubljana Bežigrad µg/m 3 n/a n/a n/a n/a 4 Maribor µg/m 3 n/a n/a n/a n/a 48 Celje µg/m Murska Sobota-Rakičan µg/m 3 n/a n/a n/a n/a 38 Nova Gorica µg/m 3 n/a n/a n/a n/a 38 Trbovlje µg/m Zagorje µg/m 3 n/a n/a n/a n/a 47 The data for Slovenia are taken from the Automatic Air Quality Measurement Database (ANAS) managed by the Monitoring Office (Environmental Agency of the Republic of Slovenia). The database is updated monthly; the data are available in their entirety upon the completion of final annual review. Following the Guidance to member states on PM1 monitoring and intercomparisons with reference method (14 September 24) the PM1 concentration values for 22 include factor