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• Variable Message Signs (Electronic Message Signs)

Frequently Asked Questions - Variable Message Signs (VMS)

The primary purpose of electronic message signs (more commonly known as Variable Message signs or VMS) on the Agency's network is to communicate information and advice to drivers about:

• Emergencies e.g Major or National Emergencies
• Incidents e.g accidents and lane closures
• Network Management e.g Roadworks.

Here we have provided the answers to some frequently asked questions regarding the electronic message signs located on our network:

Q1 What is a VMS?

Variable Message Signs (VMS) are signs located at key decisions points on the Highways Agency Network.  They display information to drivers about emergencies and incidents to improve safety and minimise the impact of congestion.

Q2 Who decides where VMS are installed?

The guiding principles for the design of motorways and trunk roads is the Design Manual for Roads and Bridges.

Volume 8, Section 2 TD 33/05 - The Use of Variable Messages Signs on All-Purpose and Motorway Trunk Roads, details the criteria for the installation of VMS.

The DMRB is available to download from the below location.

http://www.standardsforhighways.co.uk/dmrb/index.htm

Q3 Where I see the list of messages approved for use?

Details of approved VMS messages can be found in the 'Policy and Procedures for the use of Variable Message Signs by the Regional Control Centres'.  This document is available to download from the documents section of the Highways Agency VMS website.

Q4 Why does a VMS tell me there is a Queue ahead, when there is no Queue?

The Highways Agency uses a system called Motorway Incident Detection and Automatic Signalling (MIDAS) which because of sensors under the road works without human intervention.  This enables an immediate response when a queue is detected, warning motorists of slow or stationary traffic ahead.

MIDAS automatically sets advisory signs and signals to 40mph/QUEUE CAUTION to advise of the queue ahead, with a further 50mph/QUEUE AHEAD and 60mph/QUEUE AHEAD warnings before that.

Research has proven that the MIDAS system, which is installed on over 1368 km of motorway, reduces injury accidents by 13% and provides congestion benefits of 8%, leading to overall economic benefits of over £60M per year.

Q5 Why does a VMS advise a speed limit of 40 mph, even though I am in traffic that is going much slower?!

At present when a MIDAS message is displayed to warn of a queue directly ahead the system shows the lowest advisory speed limit it can set, which is currently 40mph.  As these signs are automatic, they are not switched off until the traffic has cleared.

Q6 Why do the Department for Transport (DfT) decide safety campaigns? Surely the Highways Agency manages the motorway and they know what is best?

Research commissioned by the Highways Agency has demonstrated that VMS campaigns are most effective when they are supported by other media. For this reason VMS can only be used to display campaign messages that support DfT Think! campaigns, unless special authorisation is granted from within the Highways Agency.  This authorisation can only be granted when the use of VMS is part of a communications strategy, and not the main element.

DfT Think! campaigns are designed to reinforce the need for drivers and other road users to take responsibility for their own safety and for the safety of others on the road.  These campaigns have a national overview and are designed to raise public awareness of the attitudes and behaviours, that research has shown, cause accidents.  For this reason DfT develop safety campaigns and not the Highways Agency.

There are occasions when the Highways Agency has used VMS to display other campaign messages that have not been developed by DfT, but only when these are supported via a communications strategy.  Two recent examples of Highways Agency VMS campaigns are the "Check Your Fuel Level" and "Keep Left Unless Overtaking".  Both of these were supported by press releases and marketing to raise awareness of the campaign, providing greater detail.

Q7 Why have I seen a campaign message, but no mention of an incident I am now delayed by?

VMS messages are prioritised and are automatically overwritten when a more important message needs to be displayed, such as a MIDAS message e.g. Queue Caution.  At peak travel times this means that road users are less likely to see campaign messages.

It is possible that the Highways Agency did not have information about an incident at the time a customer sees a VMS displaying a campaign message.  It is also possible that other VMS messages were displaying information about the incident in suitable numbers, so it was therefore not necessary to overwrite a campaign messages.

Q8 Major Event Signs - Surely if there is extra traffic on the motorway then drivers would benefit from knowing about it?

The Highways Agency works hard with stakeholders to identify events that are likely to cause significant congestion and/or delays on the strategic road network.  Once identified VMS messages are displayed to drivers up to a week in advance of the event to warn of the potential delays.

VMS messages are prioritised and are automatically overwritten when a more important message needs to be displayed, such as a MIDAS message e.g. Queue Caution.  At peak travel times this means that road users are less likely to see these types of messages.

Q9 Why are junction numbers shown on VMS signs and not area names? Surely people know the names of areas better?

The current policy of the Highways Agency is to display junction numbers within VMS messages, as there are a number of issues that make using names of areas on VMS difficult:

• Currently we have four sizes of VMS signs in use, displaying either 2 lines of 12 characters, 2 lines of 16 characters, 3 lines of 18 characters and a limited number of 4 lines of 12 characters.  As VMS are only able to display a small number of characters, longer place names do not fit into the space available and abbreviated names can be confusing.
• Place names indicate the location of a village, town or city only to some drivers.  There will always be a proportion of drivers who do not know the location of a named place, limiting the usefulness of the message.

Whilst using junction numbers is not a perfect solution for everybody, they do cover the motorway network fully and are prominently displayed on the motorway direction signs.  They are also included in most good maps.

The Highways Agency is in the early stages of reviewing this policy to examine how the wider use of place names can be incorporated into messages if space is available.

Q10 Can I pay to have a personal message displayed on a VMS?

Any messages displayed on VMS are "traffic signs" within the terms of section 64 of the Road Traffic Regulation Act (RTRA) 1984 and as such each one is formally authorised either by way of prescription in the Traffic Signs Regulations and General Directions (TSRGD) (6) or by special authorisation on a site-specific basis or for a specified duration only. 

The TSRGD prohibits the use of VMS for advertising.

In certain circumstances the name of events are used with messages to help provide information to drivers.  Such messages are carefully designed to ensure that they do not advertise the event, but provide drivers with information about the impact of the event, and any potential delays.

Q11 Where can I see details of your future VMS Strategy?

The Highways Agency Business Plan 09/10 details the future programme of works that the Agency plans to undertake.

This includes details of all major schemes were VMS are due to be installed.

The Business Plan is available for download at the below location.

http://www.highways.gov.uk/aboutus/22899.aspx

Q12 Why do you tell me about things that are 80 miles away? I am not going that far!

The Highways Agency carefully considers the information displayed on VMS, to enable drivers to make informed decisions.

Providing drivers with information of a delay that is still some 80 miles away allows potentially affected drivers to consider modifying their journey in a number of ways e.g. alternative routes or deciding when it is appropriate to take a break.  Delay notifications are given on VMS when delays are expected to still be occurring when taking into the travel time to the location.