The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality man...The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality management center, the CGQA</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">(Centre de Gestion de la Qualité de l’Air). Air quality monitoring at CGQA deals with mainly six pollutants: carbon monoxide (CO), nitrogen oxides (NO</span><sub><span style="font-family:Verdana;">x</span></sub><span style="font-family:Verdana;">) (with nitrogen dioxide (NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) and nitrogen monoxide </span><span><span style="font-family:Verdana;">(NO)), sulfur dioxide (SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">), ground-level ozone (O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">), Benzene-Toluene-Xylenes</span></span><span style="font-family:Verdana;"> (BTX), and particulate matters (PM) with diameters less than 10 μm (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;">) and 2.5 μm (PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">). The concentration levels of gaseous pollutants (CO, O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) in the city generally remain below the limit value set by the WHO (World Health Organization). However, particulate matters (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">) are the most important pollutants observed in Dakar, they far exceed the annual thresholds set by the WHO and the national standard (NS 05-062). This situation results in an Air Quality Index (AQI) around bad and very bad during the dry season (November to May) and good to moderate during the rainy season (June to October). The concentrations of PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;"> vary respectively from 120 to 180 μg</span></span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> and from 25 to 48 μg</span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">. The average concentrations of pollutants therefore vary from one area to another and depending on the location of the air quality monitoring station (near industrial sites, traffic, etc.).展开更多
文摘The lack of data on air quality monitoring and neglected and overlooked pollutant emissions in the transportation and industrial sectors are motives for the government of Senegal to set up, in 2009, an air quality management center, the CGQA</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">(Centre de Gestion de la Qualité de l’Air). Air quality monitoring at CGQA deals with mainly six pollutants: carbon monoxide (CO), nitrogen oxides (NO</span><sub><span style="font-family:Verdana;">x</span></sub><span style="font-family:Verdana;">) (with nitrogen dioxide (NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) and nitrogen monoxide </span><span><span style="font-family:Verdana;">(NO)), sulfur dioxide (SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">), ground-level ozone (O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">), Benzene-Toluene-Xylenes</span></span><span style="font-family:Verdana;"> (BTX), and particulate matters (PM) with diameters less than 10 μm (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;">) and 2.5 μm (PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">). The concentration levels of gaseous pollutants (CO, O</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;">, NO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and SO</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;">) in the city generally remain below the limit value set by the WHO (World Health Organization). However, particulate matters (PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;">) are the most important pollutants observed in Dakar, they far exceed the annual thresholds set by the WHO and the national standard (NS 05-062). This situation results in an Air Quality Index (AQI) around bad and very bad during the dry season (November to May) and good to moderate during the rainy season (June to October). The concentrations of PM</span><sub><span style="font-family:Verdana;">10</span></sub><span style="font-family:Verdana;"> and PM</span><sub><span style="font-family:Verdana;">2.5</span></sub><span style="font-family:Verdana;"> vary respectively from 120 to 180 μg</span></span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;"> and from 25 to 48 μg</span><span style="font-family:Verdana;">·</span><span style="font-family:Verdana;">m</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">3</span></sup><span style="font-family:Verdana;">. The average concentrations of pollutants therefore vary from one area to another and depending on the location of the air quality monitoring station (near industrial sites, traffic, etc.).