Speed limits on road traffic, as used in most countries, set the legal maximum speed at which vehicles may travel on a given stretch of road. Speed limits are generally indicated on a traffic sign reflecting the maximum permitted speed - expressed as kilometres per hour (km/h) and/or miles per hour (mph). Speed limits are commonly set by the legislative bodies of national or provincial governments and enforced by national or regional police and judicial authorities. Speed limits may also be variable, or in some places nonexistent, such as on most of the Autobahnen in Germany.
A traffic enforcement camera is a camera which may be mounted beside or over a road or installed in an enforcement vehicle to detect motoring offenses, including speeding, vehicles going through a red traffic light, vehicles going through a toll booth without paying, unauthorized use of a bus lane, or for recording vehicles inside a congestion charge area. It may be linked to an automated ticketing system.
In statistics, regression toward the mean is the phenomenon where if one sample of a random variable is extreme, the next sampling of the same random variable is likely to be closer to its mean. Furthermore, when many random variables are sampled and the most extreme results are intentionally picked out, it refers to the fact that a second sampling of these picked-out variables will result in "less extreme" results, closer to the initial mean of all of the variables.
Road traffic safety refers to the methods and measures used to prevent road users from being killed or seriously injured. Typical road users include pedestrians, cyclists, motorists, vehicle passengers, horse riders, and passengers of on-road public transport.
The regressionfallacy is an informal fallacy. It assumes that something has returned to normal because of corrective actions taken while it was abnormal. This fails to account for natural fluctuations. It is frequently a special kind of the post hoc fallacy.
Risk compensation is a theory which suggests that people typically adjust their behavior in response to perceived levels of risk, becoming more careful where they sense greater risk and less careful if they feel more protected. Although usually small in comparison to the fundamental benefits of safety interventions, it may result in a lower net benefit than expected or even higher risks.
Seat belt legislation requires the fitting of seat belts to motor vehicles and the wearing of seat belts by motor vehicle occupants to be mandatory. Laws requiring the fitting of seat belts to cars have in some cases been followed by laws mandating their use, with the effect that thousands of deaths on the road have been prevented. Different laws apply in different countries to the wearing of seat belts.
A red light camera is a type of traffic enforcement camera that photographs a vehicle that has entered an intersection after the traffic signal controlling the intersection has turned red. By automatically photographing vehicles that run red lights, the photo is evidence that assists authorities in their enforcement of traffic laws. Generally the camera is triggered when a vehicle enters the intersection after the traffic signal has turned red.
Road toll is the term used in New Zealand and Australia for the number of deaths caused annually by road accidents.
On United Kingdom roads, the term red route may refer to a stretch of road with painted red lines signifying that vehicles cannot stop there, or to a road which has historically high accident rates.
In mathematics and transportation engineering, traffic flow is the study of interactions between travellers and infrastructure, with the aim of understanding and developing an optimal transport network with efficient movement of traffic and minimal traffic congestion problems.
Bicycle safety is the use of road traffic safety practices to reduce risk associated with cycling. Risk can be defined as the number of incidents occurring for a given amount of cycling. Some of this subject matter is hotly debated: for example, which types of cycling environment or cycling infrastructure is safest for cyclists. The merits of obeying the traffic laws and using bicycle lighting at night are less controversial. Wearing a bicycle helmet may reduce the chance of head injury in the event of a crash.
Smeed's Law is an empirical rule suggested to relate traffic fatalities to traffic congestion as measured by the proxy of motor vehicle registrations and country population. The law proposes that increasing traffic volume leads to an increase in fatalities per capita, but a decrease in fatalities per vehicle.
Mobile phone use while driving is common but it is considered dangerous due to its potential for causing distracted driving and subsequent crashes. Due to the number of crashes that are related to conducting calls on a phone and texting while driving, some jurisdictions have made the use of calling on a phone while driving illegal in an attempt to curb the practice, with varying levels of efficacy. Many jurisdictions have enacted laws making handheld mobile phone use illegal. Many jurisdictions allow use of a hands-free device. Driving while using a hands-free device has been found by some studies to provide little to no benefit versus holding the device itself and carrying on a conversation. In some cases restrictions are directed only at minors, those who are newly qualified license holders, or to drivers in school zones. In addition to voice calling, activities such as texting while driving, web browsing, playing video games, or phone use in general may also increase the risk of a crash.
Intelligent speed assistance (ISA), or intelligent speed adaptation, also known as alerting, and intelligent authority, is any system that ensures that vehicle speed does not exceed a safe or legally enforced speed. In case of potential speeding, the driver can be alerted or the speed reduced automatically.
Road traffic collisions generally fall into one of five common types:
A traffic collision, also called a motor vehicle collision, occurs when a vehicle collides with another vehicle, pedestrian, animal, road debris, or other moving or stationary obstruction, such as a tree, pole or building. Traffic collisions often result in injury, disability, death, and property damage as well as financial costs to both society and the individuals involved. Road transport is the most dangerous situation people deal with on a daily basis, but casualty figures from such incidents attract less media attention than other, less frequent types of tragedy. The commonly used term car accident is increasingly falling out of favor with many government departments and organizations, with the Associated Press style guide recommending caution before using the term.
Speed limits are enforced on most public roadways by authorities, with the purpose to improve driver compliance with speed limits. Methods used include roadside speed traps set up and operated by the police and automated roadside 'speed camera' systems, which may incorporate the use of an automatic number plate recognition system. Traditionally, police officers used stopwatches to measure the time taken for a vehicle to cover a known distance. More recently, radar guns and automated in-vehicle systems have come into use.
Road speed limits in the United Kingdom are used to define the maximum legal speed for vehicles using public roads in the UK.
Road speed limit enforcement in the United Kingdom is the action taken by appropriately empowered authorities to attempt to persuade road vehicle users to comply with the speed limits in force on the UK's roads. Methods used include those for detection and prosecution of contraventions such as roadside fixed speed cameras, average speed cameras, and police-operated LIDAR speed guns or older radar speed guns. Vehicle activated signs and Community Speed Watch schemes are used to encourage compliance. Some classes of vehicles are fitted with speed limiters and intelligent speed adaptation is being trialled in some places on a voluntary basis.
