Speed Surveys
Speed Surveys
We undertake Automatic Traffic Count (ATC) based speed surveys using our MetroCount Vehicle Classifiers working with best practice guidelines to ensure we gather representative datasets.
Looking for planning permission, but the required sight-lines might be difficult to achieve?
Why not undertake a traffic flow and speed survey at the proposed site entrance to understand the speed in which vehicles are travelling on the road which may reduce the distance required for sight-lines.
Testimonial
“The survey report was a key element in the success of our planning application as it allowed us to show the sight lines in question were adequate for the operational speed of the road. I would be delighted to recommend your company to anyone looking to conduct a similar traffic speed survey.”
How it works
In general, the site-lines are typically set based on the legal speed limit on the road. However, for many roads across the country, it is not possible for vehicles to travel at the legal speed limit and therefore the sight-line distances may be reduced based on design speed of the road if a speed survey is undertaken. The design speed is the 85th percentile speed, the speed in which 85% of vehicles travel below.
To ascertain this information, IDASO would install an automatic traffic counter (ATC) which counts the number of vehicles and their speed as they cross pneumatic tubes in each direction and a sample of 100 vehicles in each direction should be captured in order to get a good representative sample.
This table indicates the typical sight-lines required based on the design speed for the road. If a speed survey is undertaken and the 85th Percentile Speed is determined, the sight-lines will then be derived from this speed and not the speed limit of the road.
Please note that the information IDASO provide is the baseline data that enables our clients to present the best case they can for their application. IDASO do not compile the finished report to be submitted with the planning. For more info, please contact us.
Interested in any of the above?
Get in touch here and we can discuss your requirements or send you more information.