A report by the Institution of Mechanical Engineers has warned that “urgent action” is needed to create a national monitoring system for air pollution.
The report highlights a number of national hotspots including the levels of NO2 in the nation’s capital and the amount of air pollution being produced from public transport around the country.
In particular the report points out that there is still more to be learnt around the levels of dust being produced throughout the London Underground network.
While the trains are electric, they can still produce metal-rich UFP from the brake linings and friction between wheel and rail. These particles can then be inhaled and absorbed deep into the lungs.
A study last year by the University of Surrey also found that concentrations of particulate matter became much higher once passengers entered underground stations.
In addition the study found that air quality levels were strongly determined by the ventilation systems found on board the trains. Concentrations were found to be higher in the tunnel sections with very high levels of PM found onboard the Northern and Victoria lines.
Despite not being able to offer any immediate solutions to the problem, the report does acknowledge that Transport for London is already working with the Committee on the Medical Effects of Air Pollutants to find a set of long-term changes that will lower the impact of this indoor air pollution on workers and passengers on the tube.
Of course the London Underground is just one part of a far larger national transport grid and an even greater air pollution problem as highlighted by the fact that 71% of local authorities failed their air quality targets in 2017.
Philippa Oldham, Lead Author of the report and Member of the Institution of Mechanical Engineers, said: “Individuals breathe in 20kg of air every day and because we can’t see it, we don’t know about the harmful particles it contains.
“The engineering community needs to develop new technology to help solve this issue, but in order to do this we need to properly understand it. We need more accurate information about what real-world emissions are and the harm that they are causing us.”
Finally, while the report places much of the responsibility on the government to increase our understanding of air pollution, it does also suggest more should be done to help encourage us to take low-emission alternatives to getting around.
“With the introduction of Clean Air Zones (CAZs) and Ultra Low Emission Zones (ULEZs) in cities, we must focus on the ease of access to public transport.” says Oldham.
“There have been notable improvements happening within our bus sector, with the nitrogen oxide (NOx) emissions from London’s bus fleet having halved in 2016 compared to 2008 levels.
This means a journey by a Euro 6 diesel car now emits ten times the per passenger NOx of a comparable journey by the latest Euro VI diesel bus. This example is something we need to learn from.”
Finally the report suggests government and local councils should do more to encourage non-motor alternatives such as walking or cycling through the creation of enhanced cycle lanes while making sure that workplaces offer better facilities including bike storage and shower rooms.