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Ordnance Survey – Great Britain's national mapping agency
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Adanac Drive
SOUTHAMPTON
United Kingdom, SO16 0AS
http://www.ordnancesurvey.co.uk/media/
07 March 2007

OS MasterMap ITN provides exceptional detail of Britain's transport network.
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Ordnance Survey today announces the latest quality figures for its most detailed geographic reference base defining Great Britain’s road network.
The national mapping agency is reporting improvements in key aspects of the currency and accuracy of the OS MasterMap Integrated Transport Network (ITN) Layer.
There are now more than 740,000 named roads in the ITN Layer with 99.21% of road links present (up 0.39% from last year). There are correct classifications of 99.70% of A roads, 99.94% of B roads and 99.93% of minor roads, bringing a true 100% digital version of Great Britain’s road network ever closer.
In October 2006 Ordnance Survey announced that customers of the ITN Layer would have access to the weight, width and height restrictions applying to road bridges in Great Britain, making it the only digital map dataset to contain such nationwide information.
"We are committed to continuous improvement in all our data based on customer need," says Ordnance Survey’s Director of Products, Peter ter Haar. "It is with the requirements of both the public and private sectors in mind that we have created a common data infrastructure on which all kinds of transport services and applications can be based. The ITN Layer offers huge potential benefits for emergency services, freight companies, hauliers, local and central government, and tens of millions of public-transport passengers and private travellers."
The quality improvements follow sustained efficiency gains in an integrated data capture policy involving Ordnance Survey field staff, enhanced technologies and a range of external sources. Around 300 surveyors, equipped with GPS kits and other precision measuring devices, each travel an average of 8,000 miles a year capturing changes to the road network – more than two million miles in all.
Ordnance Survey’s data collection resources include a national infrastructure of GPS base stations, which improve the real-time accuracy of raw satellite-based positioning from around 10 metres down to centimetre level anywhere in the country. As part of its ongoing investment in the infrastructure, Ordnance Survey recently announced new stations in the Thames Gateway region to support the massive redevelopment expected in the area in the next five to ten years.
The Integrated Transport Network (ITN) Layer is an accurate, detailed and up-to-date geographic reference base for Great Britain’s road infrastructure. Part of OS MasterMap, it complements the Topography, Address and Imagery Layers to support decision making and services benefiting from precision detail on all aspects of the transport route network.
The ITN Layer consists of two themes: the Roads Network and Road Routing Information (RRI). The Roads Network represents all navigable roads across Great Britain for those who require increasingly sophisticated geographic data to support their services and applications. The data includes road categories from motorways to alleyways, providing Department for Transport (DfT) road classifications, including trunk roads and primary routes, as well as named and unnamed minor roads and local streets. Each road link is supplied with a unique reference number – TOID – that can be shared with other users across different applications and systems.
The comprehensive RRI theme extends the product’s data functionality with features that may affect a driver’s choice of route, including height, weight and width restrictions; traffic calming; turn restrictions and one-way roads; as well as vehicular access and time restrictions.
Ordnance Survey works with a number of Licensed Partners, including systems developers and application providers, who use ITN data to create solutions to meet specific customer requirements. A list of these is available on our website www.ordnancesurvey.co.uk/partnerships.
Notes to editors
1. Ordnance Survey is Great Britain’s national mapping agency, providing the most accurate and up-to-date geographic data, relied on by government, business and the public.
2. Ordnance Survey, the OS Symbol, OS MasterMap and TOID are registered trademarks and Integrated Transport Network is a trademark of Ordnance Survey.
Press Office fax: (+44) 023 8030 5295