VAS Definition

Vehicle activated signs (VAS), are road side digital signs that display a message when they are approached by a vehicle exceeding the speed limit or going too fast for the type of road, especially when there is a hazard such as a bend or crossroads.

Introducing VAS

This page contains basic information about our vehicle activated signs. For more details about VAS please see the following VAS page links below or download our VAS good practice guide.

• Frequently asked questions about VAS
• More about VAS in Surrey, including our Surrey's framework of approved VAS suppliers
• Technical aspects of VAS
• Surrey's vehicle activated signs effectiveness study

Basic operations

• Most VAS are activated by the approach of a vehicle at a pre-set speed.
• Vehicle speed is measured by a radar, microwave device or sensors on the road.
• Some VAS can detect a vehicle’s height, weight or length.
• Surrey uses VAS along with other measures in a package approach to improve road safety.

Guidance and good practice

• The latest guidance on VAS from the Department for Transport is found in Traffic Advisory Leaflet 1/03, which can be downloaded below.
• We developed the VAS good practice guide in 2006 and updated it in 2009.

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Some frequently asked questions regarding VAS and our answers

How can I request a VAS for a road or area?

We are not currently installing VAS as there is no budget to do so. You can register your interest via our online feedback form. The decision to install a vehicle activated sign (VAS) will depend on:

• available capital funding
• available staff time
• funding to maintain the VAS
• priorities based on a detailed analysis of the collision and casualty statistics
• anticipated cost benefit if installed on a casualty reduction basis
• need for a visible reminder to drivers to lower speed

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What guidelines do you use when determining whether or not to install a VAS?

• our guidelines are specified in our VAS good practice guide
• a route survey is conducted to ensure that there are no other measures, such as upgrading of signs and lines that would improve road safety
• the proposed location must be appropriate to benefit from VAS
• casualty statistics are analysed along with traffic speed and flow data
• any possible site specific hazards are identified
• identify if the route has a history of poor compliance with the speed limit

What is a site specific hazard and how do you evaluate it?

• a site specific hazard is a certain aspect of the road which may reduce road safety
• common examples of a site specific hazard are bends or junctions
• to evaluate the site we prioritise by casualty rate and severity and confirm that the site is suitable for VAS

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Where does Surrey buy its VAS?

Our web page on VAS use in Surrey has our approved suppliers list and other information about use of VAS in Surrey.

What if I see a VAS on a road in Surrey which is broken or not functioning correctly?

Please report it to us using this online reporting form. Click on Vehicle Activated Sign to report a fault.

How can I find out more information about VAS?

If you cannot find what you're looking for regarding VAS on these pages please fill out our online feedback form and we will answer your query.