Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation
The Copenhagen Metro comprises four lines, the M1, M2, M3 and M4, with 25 subterranean stations and an additional 14 stations above ground, serving ca. 80 million passengers annually. In this study we measure fine particulate matter (PM2.5) and carbon dioxide (CO2) concentrations in stations and in...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-01-01
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| Series: | Environment International |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0160412022005487 |
| _version_ | 1797948335177334784 |
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| author | Niklas Kappelt Hugo S. Russell Dafni Fessa Keith Van Ryswyk Ole Hertel Matthew S. Johnson |
| author_facet | Niklas Kappelt Hugo S. Russell Dafni Fessa Keith Van Ryswyk Ole Hertel Matthew S. Johnson |
| author_sort | Niklas Kappelt |
| collection | DOAJ |
| description | The Copenhagen Metro comprises four lines, the M1, M2, M3 and M4, with 25 subterranean stations and an additional 14 stations above ground, serving ca. 80 million passengers annually. In this study we measure fine particulate matter (PM2.5) and carbon dioxide (CO2) concentrations in stations and in trains across the entire system. In partially underground lines, high PM2.5 concentrations with an average of 109 μg m−3 are found in below-ground stations. The observed correlation between PM2.5 concentration and distance between a station and a tunnel exit is attributed to ventilation via the piston effect. The piston effect via tunnel draught relief shafts was therefore found to be relatively limited. Filter samples of particulate matter are analysed using particle-induced X-ray emission and show an iron content of 88.6 % by mass which is quite different from above-ground particulate matter and consistent with particle production by train wheels, rails and brakes. The average concentration measured at the stations of a recently opened (2019) fully underground M3 closed loop line is 168 μg m−3, further demonstrating that while piston effect-driven ventilation is effective in close proximity to tunnel openings, it is relatively limited via tunnel draught relief shafts. Measurements onboard trains show even higher PM2.5 concentrations and the patterns in CO2 concentrations suggest carriage ventilation by tunnel air. Ventilation via doors during platform stops caused a drop in observed PM (and CO2) at stations, but the system is surprisingly polluted despite its recent construction. CO2 mixing ratios ranged from ambient to around 600 ppm. Measures should be taken to control PM levels using a combination of source control and increased clean air supply of the Copenhagen and other similar metro systems. |
| first_indexed | 2024-04-10T21:41:44Z |
| format | Article |
| id | doaj.art-adedafa7daa54be0a1ad540d0c3f0ff2 |
| institution | Directory Open Access Journal |
| issn | 0160-4120 |
| language | English |
| last_indexed | 2024-04-10T21:41:44Z |
| publishDate | 2023-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Environment International |
| spelling | doaj.art-adedafa7daa54be0a1ad540d0c3f0ff22023-01-19T04:16:03ZengElsevierEnvironment International0160-41202023-01-01171107621Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilationNiklas Kappelt0Hugo S. Russell1Dafni Fessa2Keith Van Ryswyk3Ole Hertel4Matthew S. Johnson5Department of Chemistry, Copenhagen University, DK-2100 Copenhagen, Denmark; Airlabs, Nannasgade 28, DK-2200 Copenhagen N, DenmarkAirlabs, Nannasgade 28, DK-2200 Copenhagen N, Denmark; Danish Big Data Centre for Environment and Health (BERTHA), Aarhus University, DK-4000 Roskilde, Denmark; Department of Environmental Science, Aarhus University, DK-4000 Roskilde, DenmarkDepartment of Environmental Science, Aarhus University, DK-4000 Roskilde, DenmarkAir Health Science Division, Health Canada, Ottawa K1A 0K9, Canada; Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto M5S 3E5, CanadaDanish Big Data Centre for Environment and Health (BERTHA), Aarhus University, DK-4000 Roskilde, Denmark; Department of Ecoscience, Aarhus University, DK-4000 Roskilde, DenmarkDepartment of Chemistry, Copenhagen University, DK-2100 Copenhagen, Denmark; Airlabs, Nannasgade 28, DK-2200 Copenhagen N, Denmark; Corresponding author at: Department of Chemistry, Copenhagen University, DK-2100 Copenhagen, Denmark.The Copenhagen Metro comprises four lines, the M1, M2, M3 and M4, with 25 subterranean stations and an additional 14 stations above ground, serving ca. 80 million passengers annually. In this study we measure fine particulate matter (PM2.5) and carbon dioxide (CO2) concentrations in stations and in trains across the entire system. In partially underground lines, high PM2.5 concentrations with an average of 109 μg m−3 are found in below-ground stations. The observed correlation between PM2.5 concentration and distance between a station and a tunnel exit is attributed to ventilation via the piston effect. The piston effect via tunnel draught relief shafts was therefore found to be relatively limited. Filter samples of particulate matter are analysed using particle-induced X-ray emission and show an iron content of 88.6 % by mass which is quite different from above-ground particulate matter and consistent with particle production by train wheels, rails and brakes. The average concentration measured at the stations of a recently opened (2019) fully underground M3 closed loop line is 168 μg m−3, further demonstrating that while piston effect-driven ventilation is effective in close proximity to tunnel openings, it is relatively limited via tunnel draught relief shafts. Measurements onboard trains show even higher PM2.5 concentrations and the patterns in CO2 concentrations suggest carriage ventilation by tunnel air. Ventilation via doors during platform stops caused a drop in observed PM (and CO2) at stations, but the system is surprisingly polluted despite its recent construction. CO2 mixing ratios ranged from ambient to around 600 ppm. Measures should be taken to control PM levels using a combination of source control and increased clean air supply of the Copenhagen and other similar metro systems.http://www.sciencedirect.com/science/article/pii/S016041202200548700–0199–00 |
| spellingShingle | Niklas Kappelt Hugo S. Russell Dafni Fessa Keith Van Ryswyk Ole Hertel Matthew S. Johnson Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation Environment International 00–01 99–00 |
| title | Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation |
| title_full | Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation |
| title_fullStr | Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation |
| title_full_unstemmed | Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation |
| title_short | Particulate air pollution in the Copenhagen metro part 1: Mass concentrations and ventilation |
| title_sort | particulate air pollution in the copenhagen metro part 1 mass concentrations and ventilation |
| topic | 00–01 99–00 |
| url | http://www.sciencedirect.com/science/article/pii/S0160412022005487 |
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