Skip to main content

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.

For more information on companies in this article

Related Content

  • Bluetooth and Wi-Fi offer new options for travel time measurements
    November 20, 2013
    New trials show Bluetooth and Wi-Fi signals can be reliably used for measuring travel times and at a lower cost than an ANPR system, but which is the better proposition depends on many factors. Measuring travel times has traditionally relied automatic number plate (or licence plate) recognition (ANPR/ALPR) cameras capturing the progress of vehicles travelling along a pre-defined route. Such systems also have the benefit of being able to count passing traffic and have become a vital tool in dealing with c
  • Developing new detection and monitoring technologies
    November 21, 2012
    Established detection and monitoring technologies continue to evolve, but is it time to challenge their supremacy and take a serious look at less conventional ITS? Andy Graham considers the options with Jason Barnes. For ITS system providers, the most potentially lucrative markets over the next few years are going to be the BRIC (Brazil Russia India and China) group of countries, all of which are building many miles of new roads, applying tolling to existing ones (8,000km in China alone) and implementing w
  • Wireless charging project could change perceptions of electric vehicles
    October 10, 2012
    A two-year pilot project has begun in London with taxi firm Addison Lee and electric vehicle (EV) manufacturer Renault, which uses the principle of magnetic induction to jump electricity from a base station direct to the vehicle’s battery to deliver wireless charging. The charging technology being used is called Halo and has been developed by mobile innovations company Qualcomm, the organisation responsible for processors powering the latest generation of smartphones and tablets. ‘EV drivers will opt for th
  • Dubai metro - the world's longest automated rail system
    July 31, 2012
    David Crawford reviews the recent opening of Dubai's Red Line. The US$7.6bn Dubai Metro, the Phase I Red Line of which started partial operation in September 2009, will be the world's longest driverless rail system on its planned completion in 2011. With a total length of some 75km, it will then overtake the 68.7km Vancouver SkyTrain and be able to carry over 1.2 million passengers on a typical day.