Reducing high levels of particles in tunnels

A new study from Sweden’s National Road and Transport Research Institute (VTI) which aims to improve understanding of the differences between inhalable particles in highway versus railway environments has indicated that older types of trains produce more particulate emissions in railroad tunnels than do newer ones. Dust binding, improved paving and reduced studded tyre use could reduce coarse particle levels in road tunnels.
March 1, 2017 Read time: 2 mins

A new study from Sweden’s National Road and Transport Research Institute (5230 VTI) which aims to improve understanding of the differences between inhalable particles in highway versus railway environments has indicated that older types of trains produce more particulate emissions in railroad tunnels than do newer ones. Dust binding, improved paving and reduced studded tyre use could reduce coarse particle levels in road tunnels.

The tests were carried out in Sweden at Arlanda Central station beneath Arlanda Airport and in the Söderleden road tunnel in central Stockholm. The results indicate that the environment of the studied railroad tunnel is characterised by peaks in coarse particle concentration. Some trains can be tied to emissions of ultrafine particles which consist mainly of iron, with lesser amounts of copper, zinc and other metals.

The main focus of measures to remedy high particle counts in railway tunnels has so far been on preventing exposure by separating trains from platforms or using ventilation to remove polluted air, but few studies have examined the means available to prevent the emissions themselves.

According to VTI researcher Mats Gustafsson, the study demonstrates that it is possible to reduce particulate emissions by identifying and improving train types as well as individual trains and their characteristics.

Road tunnels are characterised by high levels of ultrafine particles and high levels of coarse particles when conditions are dry. Because the traffic in such tunnels is more intense than in railroad tunnels, the particle levels are more consistently high during rush hours.

“The options available to combat coarse particles in road tunnels comprise reduced studded tyre use, better paving, and efficient dust binding and cleaning”, said Gustafsson.

The ultrafine particles that occur in high concentrations derive from vehicle exhaust and can be addressed by reducing traffic volumes, improving exhaust treatment, and lowering the proportion of heavy traffic, he says.

Air Quality & Weather Systems

Related Content

  • November 17, 2014
    Air quality tops transportation agendas
    Colin Sowman catches up on some of the latest research around outdoor pollution and looks at options available to authorities in areas of poor air quality. Iair quality hasn’t already reached the top of the agenda in transportation department meetings in your area, it probably soon will with national, trans-national and even global bodies calling for authorities to reduce pollution levels.
    Read More
  • August 8, 2018
    Knowing when to slow down
    Level 2 driver assistance vehicles have little problem reading fixed metal signs at the roadside - but it’s a different story with VMS in tunnels, finds Alan Dron. Following a series of hands-free driving tests in tunnels, an Australian road authority believes that car manufacturers have to up their game before vehicles have the required levels of competence to consistently perform ‘assisted driving’ tasks. The trials, in the state of Victoria late last year, tested the ability of several vehicles to stay
    Read More
  • April 25, 2012
    Novel Swedish approach to cell phone use while driving
    Sweden’s National Road and Transport Research Institute (VTI) is publishing a new report showing ways to improve road safety. Of note is the fact that the report does not recommend a ban on mobile phone use while driving. Instead, VTI believes that a package measures can train and support drivers to manage communications more safety. According to VTI, this will be more effective than a ban on the use of cell phones at the wheel. VTI claims that more information will enable drivers to understand when it is d
    Read More
  • October 21, 2014
    London’s strategy to tackle air quality problems
    Colin Sowman talks to Matthew Pencharz, the man charged with charting London’s path between catering for traveller needs, conserving ancient buildings and conforming to modern air quality standards.
    Read More

Highlighted Content