Road signs in Ireland

Road signs in the Republic of Ireland do not differ greatly from those used elsewhere in Europe – with the notable exception that hazard or warning signs follow the "New World" model that is employed, notably, in the Americas, Australasia, and Japan: that is to say that they feature a black symbol on the background of a yellow diamond. The symbols used on these warning signs do, nevertheless, resemble much more closely those used (on red-bordered white or yellow triangles) in the rest of Europe than many of those seen in the United States.

Regulatory signage (relating to limits and prohibitions) differs very little from that used in the rest of Europe.

The system of directional signs is based upon, and is very similar to, that employed in the United Kingdom, but is bilingual everywhere except in the Gaeltacht, where only the Irish language is used on signs.

All distances (and other measurements) are expressed in metric units. On 20 January 2005, the Republic of Ireland fully adopted metric speed limits. Around 35,000 existing signs were replaced and a further 23,000 new signs erected bearing the speed limit in kilometres per hour. To avoid confusion with the old signs, all speed limit signs include the mention "km/h" beneath the numerals.

Road signs in Northern Ireland conform in almost every respect to those used in the rest of the United Kingdom. Speed limits are signed in miles per hour and distances are displayed in imperial units.

Road signage in Great Britain is prescribed by the Traffic Signs Regulations and General Directions (the TSRGD). However, road signage in Northern Ireland is prescribed by The Traffic Signs Regulations (Northern Ireland) 1997, regulations which are currently administered by the Department for Infrastructure (the DfI), formerly known as the Department for Regional Development (the DRD).

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