Speed cameras thresholds
Freedom of information request reference no: 01.FOI.24.035798
I note you seek access to the following information:
- What are the Met's speed camera enforcement thresholds (tolerances)?
- Are they still in line with the National Police Chiefs’ Council (NPCC) guidelines of 10% + 2mph?
- Does this threshold affect all speed camera and speed trap types i.e. static flashing camera, mobile speed traps, average speed check cameras etc.?
- What are the rules for visibility of speed cameras?
- Do these rules apply to all camera and speed trap types i.e. those mentioned above? Can cameras be hidden amongst trees, bushes or vegetation?
- What are the rules for visibility of speed signage?
- Does it need to be well-lit?
- Do dual carriageways need to have signs on both sides of the road?
- Do the signs need to be of a certain size and height?
- Shouldn't there be large warning signs of a new speed limit ahead, where appropriate, before any enforcement action is taken i.e. speed cameras and NIPs being issued?
Decision
I have today decided to disclose the located information to you in full.
Please find below information pursuant to your request above.
Q1 - What are the Met's speed camera enforcement thresholds (tolerances)?
The Met’s speed camera enforcement threshold is 10% + 2mph.
The Met observes the current NPCC guidelines which states that enforcement action should commence as soon as a speed that is at +10% +2mph. This is normally the minimum speed at which enforcement is undertaken in all speed limits. The minimum speed at which a speed camera is operated may be varied at any time but there are no plans to use a threshold that is not contained in the current guidance. NPCC guidance also states that whilst tolerances exist, they do not and cannot replace police officers’ discretion.
Q2 - Are they still in line with the National Police Chiefs’ Council (NPCC) guidelines of 10% + 2mph?
It should be noted that the table of recommended speeds within the guidance contains guidelines that are additional to the table of recommended speeds. This means that speeds below those in the table may be used should the police decide to do so. The operation of devices at the speed limit +10% +2 is the current policy of MPS (see above), however, variance is also within the guidance.
Q3 - Does this threshold affect all speed camera and speed trap types i.e. static flashing camera, mobile speed traps, average speed check cameras etc.?
The threshold is the same across all safety cameras whether static or mobile enforcement. The policy outlined above is applied uniformly to all speedometers.
Q4 - What are the rules for visibility of speed cameras?
With regard to the rules for visibility of speed cameras, the Department for Transport issued guidance in 2007 in Circular (Roads) 01/2007, to guide local authorities and police forces in the use of speedometers. This had some recommendations for the visibility of speed cameras, however, the same guidance contained in paragraphs that stated, in summary:
a) The guidance was entirely optional, and
b) did not fetter or prevent the police in carrying out unmarked or covert enforcement operations, and
c) Non-compliance of the guidance on the part of the police did not, in any way, form a defence to a charge of excess speed or a traffic light offence.
Mobile enforcement vehicles and enforcement devices that are parked in the carriageway and may come into conflict with other traffic may need to have a minimum visibility distance observed, 60m up to 40mph, 100m above 40mph. This arrangement is to maintain the safety of the enforcement unit and other road users. The visibility whether compliant or not, does not form a defence to any violation record made by the non-compliant unit. It may be considered that the DfT guidance sets out “rules”, but there are no rules for how visible a speedometer needs to be. The National Police Chief’s Council publish guidance for the operation of speedometers in their Guide for the Operational Use of Speed and Red Light Offence Detection Technology. Chapter 2, Health and Safety Act applies. This guidance is also not obligatory.
Q5 - Do these rules apply to all camera and speed trap types i.e. those mentioned above? Can cameras be hidden amongst trees, bushes or vegetation?
These rules apply to all camera and speed trap types as advised in 4 above.
Q6 - What are the rules for visibility of speed signage?
The DfT guidance above refers. We would suggest that the MPS will neither confirm or deny that the use of discrete or covert speed enforcement operations are used and apply exemption for Law Enforcement S31 of the 2000 Act, with wording along the lines of:
MPS reserves the right to operate overtly, discretely and covertly as operational conditions dictate. The release of information about how, when and if these tactics are used in the speed management police has the tendency to undermine the effectiveness of the deterrent effect of the use of speed enforcement systems. The information will not be released on request. The exemption protects and reinforces the public interest.
Q7 - Does it need to be well-lit?
The rules for visibility of speed signage are that the DfT produce guidance for the deployment of road traffic signs in the Traffic Signals Manual. This is in 8 chapters/10 volumes available at: Guidance - Traffic signs manual
Chapter 3 Regulatory signs applies to speed limits. The requested information is available to you by other means so is not released to you on request. Section 21 of the 2000 Act applies. The link to the information is provided.
Q8 - Do dual carriageways need to have signs on both sides of the road?
With reference to lighting, please see The Road Traffic Regulation Act 1984, the Traffic Signs Manual and the exemption outlined at 7 above.
Q9 - Do the signs need to be of a certain size and height?
Please see the Traffic Signs Manual Chapter 3.
Q10 - Shouldn't there be large warning signs of a new speed limit ahead, where appropriate, before any enforcement action is taken i.e. speed cameras and NIPs being issued?
Please see the Traffic Signs Manual Chapter 3.
With reference to Q.10, the only requirement to enforce a speed limit is that the speed limit is either:
a) A restricted road – that will be indicated by a system of street lighting that is spaced at intervals of 200 yards (183 m) or less. The Road Traffic Regulation Act 1984 sections 81and 82 refer. Maximum speed 30 mph
b) National speed limit roads, dual and single carriageways. These have maximum speeds that differ for different classes of vehicle, with a maximum of 60 mph on a single carriageway and 70 mph for a dual carriageway or special road/Motorway.
c) A road with a speed limit other than that in a restricted road or national speed limit. These speed limits are made by a Speed Limit Order (SLO). These roads normally have a sign that is to diagram 670 or 671. The Road Traffic Regulation Act 1984 sections 84 refers.
As long as the speed limit is properly set as a national speed limit, or a restricted road, or by SLO, and the speed limits signs, if they are required, provide adequate guidance of the maximum speed on the relevant road, there is no requirement to place warning signs or signs that enforcement of the speed limit commences.
A highways authority and the police may, if they so choose, indicate the change of a speed limit before enforcement is undertaken but there is no requirement that any signs or warnings that are additional to the speed limit signs, need to be displayed before the speed limit can be lawfully enforced.