The government has commissioned a new review to ensure air quality standards and regulations are “fit for purpose” on the rail network.
It follows research conducted by the independent Rail Safety and Standards Board (RSSB) on six types of train, funded by government, which found air quality levels on some trains, while operating under diesel power, is “poorer than desired”.
The report shows measurements of pollutants including nitrogen dioxide and particulate matter throughout the duration of train journeys and found on-train concentrations of the pollutant can peak at levels ranging from one to 13 times higher than that identified next to major roads in central London.
Peaks are most often seen when trains are in tunnels or idling in stations.
According to the Department for Transport (DfT), while this is verified as within legal limits, the government wants to ensure passengers and staff can be reassured the nation’s railways meet the “very highest standards”.
It has, therefore, commissioned a review of all the regulations and standards that currently control air pollution and people’s exposure to it on the rail network, including on-board services as well as in stations.
Further research, managed by RSSB, is also expected to help better understand the scale of the air quality issue on board trains and to identify potential causes and solutions.
This will include measuring air quality levels inside a further eight train classes in service across the country’s rail network.
Rail Minister Chris Heaton-Harris said: “The safety of staff and passengers is our absolute priority. While these findings are within limits, I do not believe people should have to accept anything less than the highest levels of air quality.
“I have asked the industry to immediately conduct further research and explore all engineering modifications and options to rapidly improve air quality on trains and in stations.
“I have also launched a comprehensive review of the current standards and guidance related to air quality on the rail network. If required, we will not hesitate to strengthen legislation to ensure the highest standards of air quality are met and maintained.”