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

  • January 24, 2012
    Weigh in motion reduces road wear, increases toll revenue
    IRD, Inc's Terry Bergan discusses future applications of weigh in motion technology. The application in recent years of Weigh In Motion (WIM) at tollgates has been driven by recognition of the fact that there is economic value, which can be levied, attached to Heavy Goods Vehicles (HGVs) which haul laden (and are therefore heavy) rather than empty. As wear and damage to road surfaces increases exponentially with weight, the targeting of HGVs in particular makes sense from both the economic and maintenance p
    Read More
  • June 2, 2015
    Study finds rumble strips save lives on rural highways
    A recently completed study shows that rumble strips are proving to be an effective and low-cost way to reduce crashes on Michigan's state highways. The Michigan Department of Transportation (MDOT) started a major rumble strip program for two-lane high-speed rural highways in 2008. Centre-line and shoulder rumble strips were installed on all MDOT rural, non-freeway highways with posted speed limits of 55 mph and appropriate paved lane and shoulder widths. To date, 5,700 miles of centre-line rumble strips
    Read More
  • January 24, 2012
    Reducing incident clear up times, saving money
    In 2007 in Atlanta, Georgia, it took over four hours to open the road after a major commercial vehicle incident. Not any more. Four years ago the Texas Transportation Institute (TTI) cited Atlanta, Georgia as the third-most congested city in the United States. Each traveller in metro Atlanta lost an incredible 57 hours a year to traffic delays, wasting 40 gallons of fuel while sitting in traffic. In 2007, it took nearly four and a half hours to open travel lanes after an average tractor-trailer incident. Th
    Read More
  • April 7, 2017
    Clean diesel technology most cost-effective way to reduce emissions, officials told
    The state environmental policymakers attending the Spring Meeting of the US Environmental Council of States (ECOS) have heard how states can achieve the most cost-effective and immediate air emission reductions by targeting the largest sources of oxides of nitrogen (NOx) emissions and replacing or upgrading those with the newest generation of clean diesel technology. Allen Schaeffer, executive director of the Diesel Technology Forum, highlighted the environmental benefits of new diesel technology dur
    Read More

Highlighted Content