Graduated driver licensing systems (GDLS) are designed to provide new drivers of motor vehicles with driving experience and skills gradually over time in low-risk environments. There are typically three steps or stages through which new drivers pass. They begin by acquiring a learner’s permit, progress to a restricted, provisional or probationary license, followed by receipt of a full driver's license.
Graduated drivers' licensing generally restricts nighttime, expressway, and unsupervised driving during initial stages, but lifts these restrictions with time and further testing of the individual, eventually concluding with the individual attaining a full driver's license.
In the United States, driver's licenses are issued by each individual state and the territories (including Washington, D.C.), rather than the federal government because of the political concept of federalism. Drivers are normally required to obtain a license from their state of residence and all states recognize each other's licenses for temporary visitors subject to normal age requirements. A state may also suspend an individual's driving privilege within its borders for traffic violations. Many states share a common system of license classes, with some exceptions, and commercial license classes are standardized by federal regulation at 49 CFR part 383.
Road traffic safety refers to methods and measures for reducing the risk of a person using the road network being killed or seriously injured. The users of a road include pedestrians, cyclists, motorists, their passengers, and passengers of on-road public transport, mainly buses and trams. Best-practice road safety strategies focus upon the prevention of serious injury and death crashes in spite of human fallibility (which is contrasted with the old road safety paradigm of simply reducing crashes assuming road user compliance with traffic regulations). Safe road design is now about providing a road environment which ensures vehicle speeds will be within the human tolerances for serious injury and death wherever conflict points exist. Furthermore, the highest possible degree of safety shall be ensured when transporting goods by road. It is of vital importance to monitor and validate the road transportation safety, including comprehensive checks on drivers, vehicles and safety processes.
The basic strategy of a Safe System approach is to ensure that in the event of a crash, the impact energies remain below the threshold likely to produce either death or serious injury. This threshold will vary from crash scenario to crash scenario, depending upon the level of protection offered to the road users involved. For example, the chances of survival for an unprotected pedestrian hit by a vehicle diminish rapidly at speeds greater than 30 km/h, whereas for a properly restrained motor vehicle occupant the critical impact speed is 50 km/h (for side impact crashes) and 70 km/h (for head-on crashes).
Automobile safety is the study and practice of design, construction, equipment and regulation to minimize the occurrence and consequences of automobile accidents. Road traffic safety more broadly includes roadway design. One of the first formal academic studies into improving vehicle safety was by Cornell Aeronautical Labs of Buffalo, New York. The main conclusion of their extensive report is the crucial importance of seat belts and padded dashboards. However, the primary vector of traffic-related deaths and injuries is the disproportionate mass and velocity of an automobile compared to that of the predominant victim, the pedestrian.]citation needed[ In the United States a pedestrian is injured by an automobile every 8 minutes, and are 1.5 times more likely than a vehicle's occupants to be killed in an automobile crash per outing.
Improvements in roadway and automobile designs have steadily reduced injury and death rates in all first world countries. Nevertheless, auto collisions are the leading cause of injury-related deaths, an estimated total of 1.2 million in 2004, or 25% of the total from all causes. Of those killed by autos, nearly two-thirds are pedestrians. Risk compensation theory has been used in arguments against safety devices, regulations and modifications of vehicles despite the efficacy of saving lives.