Request ID: FOI-1204-2324 Date published: 10 August 2023
You asked
I would like to know the exact locations of all the underground venting ports that vent the underground “air” back into overground London please.
We answered
TfL Ref: FOI-1204-2324
Thank you for your request which we received on 16 July 2023, asking for the location of London Underground ventilation shafts that vent out air above ground.
Your request has been considered in accordance with the requirements of the Environmental Information Regulations (EIRs) and our information access policy. I can confirm that we hold the information you require.
However, we consider that releasing a list of all the tube ventilation shaft points into the public domain would be prejudicial to national security and public safety, through the knowledge of where access to the London Underground may be gained, outside our normal controlled routes.
This information is exempt from disclosure by virtue of Regulation 12(5)(a) of the EIRs, which provides that information can bewithheld when its disclosure would adversely affect internationalrelations, defence, national security or public safety.
Although some of this information you asked about is already publicly available and some points can be identified above ground by those who know what they are looking for, this is quite different from TfL knowingly and deliberately making all this information available in a single list. It is an important principle of the FOIA and EIRs that disclosures are considered to be made to the general public and not just to the person making the request.
Disclosure of this information could assist any persons wishing to disrupt London’s transport infrastructure by placing into the public domain information which would otherwise not be available via other means. This information would be of considerable use to anyone planning terrorist attacks on the London Underground network, for example, which would have clear consequences for public safety. The risk of such attacks is clearly not a hypothetical or remote possibility. There is a real and ongoing risk, particularly of terrorist attack, on the London Underground, and we must take reasonable steps to safeguard the security of our staff and the travelling public.
Regulation 12(5)(a) is a qualified exception, which means that TfL must consider the balance of the public interest. While we appreciate the expectation of transparency from public bodies, in this instance we do not consider that there are any other significant factors in favour of the release of this information. On the other hand, there are significant public interest factors in favour of limiting the amount of extra operational information that is made public as outlined above.
Please see the attached information sheet for details of your right to appeal.
Yours sincerely
Eva Hextall FOI Case Management Team General Counsel Transport for London
