Carbon monoxide (CO) and hydrocarbon (HC) emissions are checked during vehicle MOTs and new technology has been developed for modern vehicles to reduce CO and particulate emissions to meet the more stringent exhaust regulations.
But although greater efforts have been made to reduce exhaust emissions, there are other sources of pollution from vehicles that are not taken into account – and these are becoming more important in managing our air quality.
New research led by Professor Ranjeet Sokhi, from the University of Hertfordshire’s Centre for Atmospheric and Instrumentation Research (CAIR), shows that vehicle exhausts only account for one third of traffic pollution – with nearly a half of air pollution from road traffic being due to non-exhaust sources such as brake wear, road surface wear and particles whipped up from the road by passing vehicles.
They took samples from a more controlled environment where the weather had a lot less influence – and the Hatfield Tunnel proved to be an ideal location to collect the material for analysis!
The study, Source apportionment of traffic emissions of particulate matter using tunnel measurements, is published in Atmospheric Environment. It was part of a PhD project undertaken by Samantha Lawrence and funded by the Natural Environment Research Council (NERC) and the British Oxygen Company (BOC).
Image credits:Motorway Traffic- Credit Maxwell Hamilton under a Creative Commons Attribution-Share Alike 2.0 Generic license. Hatfield Tunnel - Credit Brian Green under a Creative Commons Attribution-Share Alike 2.0 Generic license.