This request is in regards to average speed camera on A40 between Perivale Lane UB6 to A40 A312 Church Road UB5. In a previous FoI request published online, it was stated that the average speed cameras were set to 40mph to cover the area where the speed limit has been reduced. Namely where the barriers have been found to be unsuitable for higher speeds. However, the location where the speed limit is reduced from 50mph to 40mph is in between two sets of cameras. This suggests it is impossible to accurately measure the average speed of vehicles relative to the two speed limits. Therefore my questions under the Freedom of Information Act are as follows: 1. Can you confirm how these two speeds are measured? 2. How many penalties have been issued to drivers speeding in this section of the road in the past year? 3. What is the lowest speed at which a penalty has been issued?

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TfL Ref: 0645-1920

Thank you for your request received by Transport for London (TfL) on 31 May 2019 asking for information about Average Speed Cameras on the A40.

Your request has been considered in accordance with the requirements of the Freedom of Information (FOI) Act and our information access policy. I can confirm we do hold some of the information you require. You asked:

1. Can you confirm how these two speeds are measured? 2. How many penalties have been issued to drivers speeding in this section of the road in the past year? 3. What is the lowest speed at which a penalty has been issued?

In accordance with the FOI Act, we are not obliged to provide the information you seek regarding the average speed camera operations as this information is subject to a statutory exemption to the right of access to information under section 31(1)(b) and Section 31(1)(g), which exempt from disclosure information which would, or would be likely to prejudice the apprehension or prosecution of offenders or the exercise of functions for the purpose of ascertaining whether any person has failed to comply with the law.

A disclosure made under FOI is deemed to be a disclosure ‘to the world at large’. Disclosing the information you are requesting, would provide public knowledge on how the cameras operate which could undermine compliance with traffic restrictions at those locations.

The purpose of enforcement is to deter drivers from contravening restrictions that are in place and penalties are issued accordingly. Any decrease in compliance creates a risk to the safety of all road users. 

The use of this exemption is subject to an assessment of the public interest in relation to the disclosure of the information concerned. We recognise the need for openness and transparency by public authorities, but in this instance feel that balance lies in favour of withholding the information to ensure that we are able to achieve Vision Zero of no-one killed or seriously injured on London’s roads.  

With regards to your question about how many penalties have been issued to drivers speeding in this section of the road in the past year, we don’t hold this information which is held by the Metropolitan Police Service. You can contact them at: https://www.met.police.uk/foi-ai/accessing-information/.

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.

Yours sincerely

Sara Thomas

FOI Case Management Team

General Counsel

Transport for London

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