Research and analysis

London Underground: video about a study into how air flows around the network

Video about a study conducted in June 2013 to increase our understanding of how air flows around the London Underground network.

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Airflow studies on the London Underground network

This short film provides information about a study of airflow across the London Underground network as conducted in June 2013 by the Department for Transport, supported by London Underground and the British Transport Police.

More detail of the equipment and how the airflow will be measured and monitored is described in a further short film.


Voice over: Between 17 and 28 June the Department for Transport will be conducting a study of airflow over the London Underground network.

The study forms part of a research project to help us check and better understand how air flows on the Underground.

A similar, small scale, study was carried out at St John’s Wood tube station in 2007.

This time, the study will be carried out at a various locations within a number of underground stations.

Nigel: The stations aren’t being closed in this test because we needed as realistic environment as possible. So the trains will keep moving, the stations will keep operating and people will pass through those stations, that way we get realistic results. We can use those results in our safety and security plans for the Underground.

There will be absolutely no disruption as a result of this study. What people will see is some monitoring equipment on some stations.

We’re doing the test on 5 days over a 2 week period.

Dean: The purpose of the study is to monitor airflow on the London Underground.

…to improve our emergency responses in the case of an incident on London Underground.

…we previously developed a computational model but we needed to do experimental trials to confirm that model is accurate and develop it further.

We’ve got 2 main types of tracer materials, one is based upon gases

but there are several other tracers called perfluorocarbons. And then we have the particulate tracer.

They are all established tracer materials, that have been used elsewhere, and they’ve all been demonstrated as being safe and harmless and that’s been confirmed by the Chief Medical Officer.

Nigel: We’ve got posters at stations that give a little bit of information, if people want to find out more, they should visit the Department for Transport’s website. There’s a lot more information there about the trials, why they’re being conducted and how they’re being conducted.

Voice over: This is a routine study, but should you have any questions or concerns please contact us at the following email address or call us on 0300 330 3000.

Published 17 June 2013