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At a time when many nations are still debating the proper demployment of technology for traffic management and safety on the roads, Britain has shown that proper use of cameras can significantly lower casualties. This proves that the hesitant utilisation of technologies needs to be replaced with focused strategies on an urgent basis.
BRITAIN’S roads are among the safest in the world and this success is largely due to the range of enforcement technology in use as it has played a crucial role in reducing road casualties.
Deployed as a part of a research-based road safety strategy, the technology has helped to reduce deaths and injuries significantly year on year. According to the Department for Transport (‘Transport Statistics, Great Britain 2011’), 1850 people had died and 22,660 seriously injured on Britain’s roads in 2010. Ten years earlier, these figures were almost double.
Road safety practitioners, including police officers, police staff and local government employees, have access to a range of enforcement technology which has evolved considerably over recent years. This technology consisting of fixed spot, red-light, mobile safety cameras and average speed camera systems, has been highly successful in affecting driver behaviour. That has resulted in lowering vehicle speeds and reducing road casualties.
The various types of enforcement technology are tools in the road casualty reduction ‘toolbox.’ The ongoing casualty and collision monitoring allows practitioners to use the correct tool to tackle a particular problem effectively. A study, ‘The Effectiveness of Speed Cameras – A Review of Evidence’, conducted by independent transport researcher Professor Richard Allsop in 2010 showed that if safety cameras were to be removed from Britain’s roads, a staggering 800 more people would have been killed or seriously injured each year.
Once in use, the safety cameras deter drivers from speeding and carrying out other dangerous activities behind the wheel. The defaulters detected by a camera face a fine of £60 and three driving licence penalty points. In case their offences are particularly excessive, their cases are sent to the courts. The threat of these repercussions has a significant impact on driver behaviour. Apart from reducing road casualties, safety cameras bring about a reduction in the average speeds, maintain traffic flow, assist in the reduction of CO2 emissions and improve the citizen well-being in general.
Enforcement Technology in use in Britain
Fixed Spot Safety Cameras
Spot fixed safety cameras target a particular ‘spot’ on the routes that have a history of casualties and are effective in altering the driving behaviour in the vicinity of the camera. Traditionally, the technology used wet film but it is now being gradually replaced with digital alternatives.
The speed of the subject vehicle is assessed by various methods – radar, sub-surface vehicle sensors or laser. Radar systems, commonly called across-the-road radar, use a continuous wave radar beam set at a fixed angle to the road. The subject vehicle travels through the beam causing a Doppler shift to be imparted on the signal that is proportional to the vehicle speed. The speed is assessed many times; each needing to agree within close limits to assure no anomalous readings is acquired. Once the system has decided the speed is correct and faster than a pre-set threshold, a photographic record is made of the vehicle details and the speed recorded.
A laser system will use well established statistical techniques to assess the speed of a subject vehicle as it travels past a fixed spot in the road. The statistical techniques employed by laser systems provide a high degree of assurance that the speed is correct before it is declared valid triggering photographic records similar to those in the radar system.
Sub-surface sensors can be used to assess vehicle speed in place of radar or laser. It is common for two or three sub-surface sensors to be placed at right-angles to the vehicle path at a fixed and known distance. As the vehicle passes over the sensor, pulses are returned to the speedmeter system that are stored and timed. The time between the pulses is used with the distance between the sensors to calculate the speed of the vehicle by a distance/time formula. In common with other speedmeters, the speed is assessed on more than one occasion. For instance, between sensor 1 to 2 and then sensor 2 to 3, the results will be compared and will be required to be close to the same value.
Unattended speedmeters used in the UK are required to have a second form of speed measurement to verify the primary method because it is improbable that a fault in the primary method will give an error that is the same error as a fault in the secondary measurement. The secondary method gives a high degree of assurance that the primary method has performed accurately and as expected at the time of the speed measurement. In this way, the speeds produced by an unattended speedmeter require no witness at the scene or at the time of the incident.
