Average speed control
Average speed control (also called ‘section control’ or ‘point-to-point’ control) is a relatively new speed enforcement technique. Average speed control systems measure the average speed over a road section (usually 2 – 5 km). The vehicle is identified when entering the enforcement section, and again when leaving it. The average speed can be calculated based on the time interval between these two points.
Average speed control works 24 hours a day, 7 days a week, which means the chance of being caught is close to 100 percent. On a stretch of road where average speed control is employed, most drivers obey the speed limit. On sections where speed limits were frequently exceeded in the past, average speed control can bring back the number of offences to a few percent, or even less than one percent.
Average speed control is still fairly new, not yet widely applied and not yet evaluated on a substantial scale. In Austria, Stefan  evaluated the use of average speed control on an 80 km/h motorway stretch running through a tunnel. In its first year of operation, a reduction in average speed by more than 10 km/h was recorded. Stefan estimated that after two years of operation average speed control reduced injury crashes by 33.3% and fatal and serious injuries by 48.8%. Taking into account both effects on road safety and road traffic emissions, Stefan computed a cost-benefit ratio of average speed control of 1:5.3. Positive results with section control were also obtained in the Netherlands. It was found that average speed control reduced the number of speed offenders to less than 1% at an enforced section of motorway .