Traffic sign

Most countries place signs, known as traffic signs or road signs, at the side of roads to impart information to motorists and other road users. Since language differences can create barriers to understanding, international signs using symbols in place of words have been developed in Europe and adopted in most countries and areas of the world. Annex 1 of the Vienna Convention on Road Signs and Signals of November 8, 1968 defines eight categories of signs:

• A. Danger warning signs
• B. Priority signs
• C. Prohibitory or restrictive signs
• D. Mandatory signs
• E. Special regulation signs
• F. Information, facilities, or service signs
• G. Direction, position, or indication signs
• H. Additional panels

Countries and areas categorize road signs in different ways. The categories used in the United States are:

• Regulatory signs
• Warning signs
• Marker signs
• Guide and informational signs
• Recreational and cultural interest signs
• Signs for bicycle facilities
• Construction signs
• Railroad crossing signs
• School signs
• Civil defense signs

History

A road sign near Bristol, England, giving directions to Parkway railway station (red symbol), motorways (blue backgrounds) and an assortment of A roads (major roads). The red outline is used for military establishments (the Ministry of Defence at Abbey Wood). The bracketed numbers indicate destinations reachable by routes accessed via the unbracketed roads listed.

The earliest road signs gave directions, for example the Romans erected stone columns throughout their empire giving the distance to Rome. In the Middle Ages multidirectional signs at intersections became common giving directions to cities and towns.

Traffic signs became much more important with the development of automobiles and their faster motion. The basic patterns of most traffic signs were set at the 1908 International Road Congress in Rome. Since then there have been considerable change in signs. Today there are almost all metal rather than wood and are coated in a thin film filled with small glass particles that make them highly reflective (see retroreflection).

Design

North America and Australia

Warning signs are one of the important types of traffic signs

In North America and Australia, signs generally adhere to the following colours:

• green with white letters for informational signs, such as directions, distances, and places
• brown with white for signs to parks, historic sites, ski areas, forests, and campgrounds
• blue with white for rest areas, food, gasoline or petrol, and lodging
• white with red or black letters for regulatory signs, such as speed limits or parking
• yellow with black letters and symbols for warning signs, such as curves and school zones
• orange with black letters for construction zones and detours

Regulatory signs are also sometimes seen with white letters on red or black signs. In Québec, the usage of blue and brown is reversed, and many black-on-yellow signs are red-on-white instead. Many U.S. states now use fluorescent orange for construction signs, and fluorescent yellow for school zone and crosswalk signs.

Every state and province has different markers for its own highways, but use standard ones for all federal highways. Many special highways, such as the QEW or Trans-Canada Highway, or originally on U.S. highways like the Dixie Highway, have used completely unique signs. Counties in the U.S. sometimes use a pentagon-shaped blue sign with yellow letters for numbered county roads, though the use is inconsistent even within states.

American road signs measure distances in miles rather than kilometres. Traffic signs in the United States have been standardized through the Manual on Uniform Traffic Control Devices (MUTCD), though they sometimes still vary from state to state, particularly on older signs.

United Kingdom

Europe

Central and South America

Asia

People's Republic of China

Traffic signs in simplified Chinese and partly in English on Chinese expressways.

Mainland China uses simplified Chinese characters for its traffic signs. It is gradually moving toward internationally-accepted signs; it ditched, for example, a localised version of the "no parking sign" (with a Hanzi character) and used the blue-red cross sign as of the late 1990s.

In larger cities and on expressways of China, both English and Chinese are used.

Hong Kong Special Administrative Region

Traffic signs in Hong Kong.

Although the mainland uses simplified Chinese characters, traditional Chinese characters are still used in Hong Kong (as the policy of "one country, two systems" allows Hong Kong to maintain most affairs, including road traffic regulations, the way they were prior to the handover.)

Most, if not all, of Hong Kong's signs are bilingual, as English and Chinese are both considered official languages. English often appears on top of text in traditional Chinese.

Africa

See also: street sign theft

External links

• French traffic signs according to la sécurité routière web site (France) (http://www.securiteroutiere.gouv.fr/IMG/pdf/LesSignauxRoutiers-2.pdf) in french
• international Convention about traffic sign ( governemental swiss website) (http://www.admin.ch/ch/f/rs/0_741_20/) in french

• http://www.unece.org/trans/conventn/legalinst.html -- Legal instruments in the field of transport -- Number 10 is the Convention on Road Signs and Signals, of 8 November 1968, including the annexes.
• http://homepages.cwi.nl/~dik/english/traffic/ -- Excellent collections of international road traffic signs
• http://members.aol.com/rcmoeur/signman.html -- Unofficial Manual of Traffic Signs in the United States

de:Verkehrszeichenes:Señales de tráficonl:Verkeersbord fr:panneau de signalisation routière