Excessive Speed

Road speed inhibitions are utilized in most countries to set the maximum (or minimum in some cases) speed at which road conveyances may licitly peregrinate on particular stretches of road. Speed limits may be variable and in some places speeds are illimitable. Speed constraints are mundanely betokened on a traffic sign. Speed inhibitions are commonly set by the legislative bodies of nations or provincial regimes and enforced by national or regional police and / or judicial bodies.

The first maximum speed circumscription was the 10 mph (16 km/h) limit introduced in the Amalgamated Kingdom in 1861. The highest posted speed limit in the world is 140 km/h (87 mph), which applies to some roads in Poland and Bulgaria; similarly Texas posts 85 mph (137 km/h) on one 40-mile (64 km) long toll road. However, some roads have no speed limit for certain classes of conveyances. Best kenned are Germany's less congested Autobahns and areas of Australia's Stuart Highway. where automobile drivers have no mandated maximum speed; quantifications from the German State of Brandenburg in 2006 showed average speeds of 142 km/h (88 mph) on a 6-lane section of autobahn in free-flowing conditions. Rural areas on the Isle of Man, the Indian states of Andhra Pradesh, Maharashtra, and Telangana, withal lack speed limits, but speeds are lower when quantified on those lower design roads.

Speed constraints are customarily set to endeavor to cap road traffic speed; there are several reasons for wanting to do this. It is often done with an intention to amend road traffic safety and reduce the number of road traffic casualties from traffic collisions. In their World report on road traffic injury aversion report, the World Health Organization (WHO) identify speed control as one of sundry interventions liable to contribute to a reduction in road casualties. (The WHO estimated that some 1.2 million people were killed and 50 million injured on the roads around the world in 2004.)Speed limits may additionally be set in an endeavor to reduce the environmental impact of road traffic (conveyance noise, vibration, emissions) and to gratify local community wishes for streets utilizable by people out of cars. Some cities have reduced limits to as minute as 30 km/h (19 mph) for both safety and efficiency reasons.

In situations where the natural road speed is considered too high by regimes, eminently on urban areas where speed limits below 50 km/h (31 mph) are utilized then traffic calming is often withal utilized. For some classes of conveyance, speed limiters may be mandated to enforce compliance.

Since their prelude, speed limits have been opposed by some motoring advocacy groups.