The opinions expressed in the studies are those of the consultant and do not necessarily represent the position of the Commission.
A speed limit is based on both safety and mobility considerations and increasingly also on environmental considerations. The general framework for speed limits is the responsibility of the national government. Generally, local and regional road authorities determine the speed limit on a particular road. The current general speed limits vary across EU Member States. Also the application of variable speed limits related to traffic and weather conditions vary across EU Member States
Safety is only one element that affects what speed limit is applied. Also the effects on travel time, mobility must be considered. Setting limits aims to meet the optimum total cost by balancing safety and mobility consequences. There may be a different optimum for different roads depending on their accident rate and their function for mobility. What the optimum is, is largely determined by the method and assumptions that are applied to calculate the costs of road accidents and mobility loss, and increasingly also the costs of air pollution and noise. This, in the end, is a political decision. Assessment frameworks have been proposed to support these decisions .
Some administrations  are now proposing that the "balance" between safety and mobility should be judged from a more ethical standpoint. This requires that an upper limit is put on the injury risk that could occur on the road (e.g. virtually eliminating the chance of a fatality occurring). The speed limit and the design of the road infrastructure would then be matched to ensure that the injury risk was not exceeded.
Clearly, there are differences between countries in the way that speed limit setting is arranged. Generally, the national government decides on the general, national speed limits for different road types. The national government may also determine which exceptions to the general limits can be applied. It generally is the road authority that decides what speed limit is applied for a specific road or road section in their jurisdiction. This decision, of course, must fit within the national speed limit framework. It means, however, that local or regional road authorities have a large amount freedom in determining which speed limit would be applied where.
A common approach to determine the most appropriate speed limit for a particular road or road section is to set the limit close to the V85. The V85-speed is the speed that is not exceeded by 85% of the vehicles. Ideally, however, the speed limit should be based on an analysis of the road and traffic characteristics to make sure that the limit represents a safe speed and, in addition, that the limit is a credible limit for the majority of drivers.
The general speed limit for motorways in EU Member States is mostly 120 or 130 km/h. Germany does not have a general speed limit for motorways, but a recommended speed of 130 km/h. The general speed limit for rural roads in EU Member States is mostly 80 or 90 km/h and for urban roads 50 km/h.
In most countries speed limits that differ from these general limits are applied. Widespread and well known are the 30 km/h zones in residential areas. In Germany, where there is no general speed limit for motorways, many sections of the motorway have a local posted speed limit which may range from 80 km/h to 130 km/h, related to both safety and environmental considerations. Also in the Netherlands, an increasing number of motorway sections have a permanent lower speed limit (notably 100 or 80 km/h) aiming to reduce air pollution and noise where there are adjacent residential areas.
EU countries apply a lower speed limit for heavy good vehicles (HGVs) and buses/coaches. The majority of countries only apply an overall maximum speed limit for HGVs (generally 80 km/h) and buses (varying between 80 and 100 km/h). By EU-Directive 92/24/EEC and its recent adaptation (2004/11/EEC), speed limiters are compulsory for HGVs of 3.500 kg and more and for buses of 10.000 kg or more. Some countries apply lower HGV and bus speed limits for different road types (e.g. Denmark, Ireland and the United Kingdom).
In the EU, only France applies lower general speed limits for bad weather conditions. In case of rain or snow, the speed limit for motorways changes from 130 km/h to 110 km/h and at rural roads from 90 km/h to 80 km/h. In case of fog (visibility less than 50 meters) the speed limit on all types of roads is 50 km/h. In other countries (e.g. Germany, United Kingdom) matrix signs on motorways provide advisory or compulsory reduced speed limits when weather conditions are bad.
Both Finland and Sweden apply different general speed limits in wintertime. In Finland, the speed limit at motorways changes from 120 km/h to 100 km/h and, on main rural roads, from 100 km/h to 80 km/h; these have been evaluated by Peltola . Similarly in Sweden the speed limits change respectively from 110 km/h to 90 km/h and from 90 km/h to 70 km/h.
In France, it is common to reduce the general speed limit by 20 or 30 km/h on a temporary basis, generally in case of high temperatures, with the aim to reduce air pollution and smog.