All the vehicle detection technologies discussed above have been implemented worldwide for the
purposes of collecting traffic data. Figure 3.1 shows worldwide detection technologies for
permanent installation based on vehicle detection market share in 2002 (Stewart et. al. 2006).
Inductive loops are the most prevalent vehicle detection technology in Australia. Magnet sensors
and infrared sensors are the new sensors that can be used alongside inductive loops in Australia
and New Zealand. Other vehicle detection technologies discussed are either not appropriate for
freeway conditions or do not offer any significant advantages over inductive loops.