![Empty tunnel under construction for the metro. Large temporary ventilation pipe under the ceiling subway tunnel. Focus on the center of the frame Stock Photo - Alamy Empty tunnel under construction for the metro. Large temporary ventilation pipe under the ceiling subway tunnel. Focus on the center of the frame Stock Photo - Alamy](https://c8.alamy.com/comp/JJGRXF/empty-tunnel-under-construction-for-the-metro-large-temporary-ventilation-JJGRXF.jpg)
Empty tunnel under construction for the metro. Large temporary ventilation pipe under the ceiling subway tunnel. Focus on the center of the frame Stock Photo - Alamy
![PDF] MEANS TO IMPROVE METRO STATION ENVIRONMENT WHEN VENTILATION SHAFTS ARE IN CLOSE PROXIMITY TO PLATFORMS | Semantic Scholar PDF] MEANS TO IMPROVE METRO STATION ENVIRONMENT WHEN VENTILATION SHAFTS ARE IN CLOSE PROXIMITY TO PLATFORMS | Semantic Scholar](https://d3i71xaburhd42.cloudfront.net/004680b00d100f43f54486bbdea0eb69c82009e5/5-Figure3-1.png)
PDF] MEANS TO IMPROVE METRO STATION ENVIRONMENT WHEN VENTILATION SHAFTS ARE IN CLOSE PROXIMITY TO PLATFORMS | Semantic Scholar
![File:Ventilation shaft of Geologicheskaya metro station (Венткиоск станции Геологическая) (6969304453).jpg - Wikimedia Commons File:Ventilation shaft of Geologicheskaya metro station (Венткиоск станции Геологическая) (6969304453).jpg - Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/thumb/d/d7/Ventilation_shaft_of_Geologicheskaya_metro_station_%28%D0%92%D0%B5%D0%BD%D1%82%D0%BA%D0%B8%D0%BE%D1%81%D0%BA_%D1%81%D1%82%D0%B0%D0%BD%D1%86%D0%B8%D0%B8_%D0%93%D0%B5%D0%BE%D0%BB%D0%BE%D0%B3%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B0%D1%8F%29_%286969304453%29.jpg/320px-Ventilation_shaft_of_Geologicheskaya_metro_station_%28%D0%92%D0%B5%D0%BD%D1%82%D0%BA%D0%B8%D0%BE%D1%81%D0%BA_%D1%81%D1%82%D0%B0%D0%BD%D1%86%D0%B8%D0%B8_%D0%93%D0%B5%D0%BE%D0%BB%D0%BE%D0%B3%D0%B8%D1%87%D0%B5%D1%81%D0%BA%D0%B0%D1%8F%29_%286969304453%29.jpg)
File:Ventilation shaft of Geologicheskaya metro station (Венткиоск станции Геологическая) (6969304453).jpg - Wikimedia Commons
![This is how the subway is „breathing” | Official website of the reconstruction project <br>of metro line M3 This is how the subway is „breathing” | Official website of the reconstruction project <br>of metro line M3](https://m3felujitas.hu/sites/default/files/imce/F%C5%91szell%C5%91z%C5%9111.jpg)
This is how the subway is „breathing” | Official website of the reconstruction project <br>of metro line M3
![Numerical modeling of the piston effect in longitudinal ventilation systems for subway tunnels - ScienceDirect Numerical modeling of the piston effect in longitudinal ventilation systems for subway tunnels - ScienceDirect](https://ars.els-cdn.com/content/image/1-s2.0-S0886779813001387-gr5.jpg)
Numerical modeling of the piston effect in longitudinal ventilation systems for subway tunnels - ScienceDirect
![Schematic diagram of the ventilation system for two-way subway running... | Download Scientific Diagram Schematic diagram of the ventilation system for two-way subway running... | Download Scientific Diagram](https://www.researchgate.net/publication/312272145/figure/fig1/AS:451330738266112@1484617041102/Schematic-diagram-of-the-ventilation-system-for-two-way-subway-running-tunnels-operating.png)