Results of the mayor's effort to reduce pollution on the tube
Request ID: FOI-1379-2324 Date published: 17 August 2023
You asked
In 2017 you announced that the mayor launched a £875m programme to clean the air on the tube (https://tfl.gov.uk/info-for/media/press-releases/2017/june/mayor-launches-plan-to-improve-air-quality-on-the-tube).
A number of measures are detailed in the announcement, and I was wondering if you could provide information on the following:
1. What measures have been put in place, and in which stations?
2. Have any of the initially proposed solutions turned out to be discarded because impractical/too expensive/any other reason?
3. Could you provide data on the amount of dust and particles (eg PM2.5) in the stations and tunnels over the past 5 or 10 years, and show to which extent your measures have reduced pollution?
We answered
TfL Ref: 1379-2324
Thank you for your request received by Transport for London (TfL) on 30 July 2023 asking for information about air on the tube.
Your request has been considered in accordance with the requirements of the Environmental Information Regulations and our information access policy. I can confirm that we hold the information you require. Your questions and our respective replies are as follows:
1. What measures have been put in place, and in which stations?
We would like to clarify that the £875m you refer to is for all air quality improvements across the whole of TfL which includes the improvements to air quality on the London Underground.
We have a robust three pillar programme of work to tackle Tube dust: funding of world-leading research; cleaning and monitoring; and utilising the latest advances in innovation. We take a strategic approach to Tube dust to reduce dust levels in areas of the transport network which are most affected. We assess and grade the tracks, with cleaning targeted at the priority locations and the tracks cleaned are different each year. Track cleaning supervisors are now carrying out air quality monitoring from within the train carriage every two months - providing a constant view of the overall dust levels on the network. We have also increased our annual Tube dust cleaning budget by a third, to £2 million. We undertake annual dust monitoring at 24 locations, details of the locations and results are published on the TfL website: https://tfl.gov.uk/corporate/publications-and-reports/environment-reports
2. Have any of the initially proposed solutions turned out to be discarded because impractical/too expensive/any other reason?
We are exploring the latest innovations, including understanding approaches taken by colleagues across the globe, with the launching of London Tube dust innovation challenges and working with Community of Metros (CoMET). We have been exploring various potential technical solutions, however have found that they are either not suitable for the London Underground and the content of the dust produced or scaleable to make a meaningful difference to the levels. Careful consideration goes into the practicality of teams being able to use it during the cleaning process and whether it can be placed in a location where it is serviceable and can actually capture the airborne particulates.
3. Could you provide data on the amount of dust and particles (eg PM2.5) in the stations and tunnels over the past 5 or 10 years, and show to which extent your measures have reduced pollution? Thank you.
Our monitoring has shown that dust levels on the Tube remain well below occupational limits set by the Health and Safety Executive (HSE) and levels on most of our network are below the recommendations from the Institute of Occupational Medicine, which are set significantly lower. While dust matter above the ground in urban environments can be made up of some components known to be harmful to health, the main component of Tube dust, iron oxide, is not currently known to be harmful in this way. Our reports can be found on the following link: - https://tfl.gov.uk/corporate/publications-and-reports/environment-reports
If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.
Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed.
Yours sincerely
Sara Thomas FOI Case Management Team General Counsel Transport for London
