Traffic Calming

Traffic Calming schemes are funded by TII to improve the safety of national roads where they pass through towns and villages. It has been found that posting speed limits without any physical speed reducing measures does not induce drivers to sufficiently reduce their speed in towns and villages. Traffic calming aims to reduce vehicle speeds in urban and residential areas by self-enforcing traffic engineering methods. Traffic calming improves the safety of urban sections of national roads by reducing speed, and therefore reducing the frequency and severity of collisions at these locations.

The speed reductions are achieved by altering the appearance of the road on the approach to the town through the use of "gateways" and are maintained by further traffic management arrangements within the town itself. The primary criteria applied in selecting towns and villages for traffic calming are the number and severity of collisions.

TII first issued guidelines on traffic calming in 1998, and have since been revised in August 2018 to make reference to the Design Manual for Urban Roads and Streets. The publication is available online here. TII manages an ongoing traffic calming maintenance contract for the maintenance of the various traffic calming schemes on national roads throughout the country.