Speed Studies

Speed studies are undertaken to:

• Assess the compliance with existing speed zoning;
  

• To determine the best location to install buffer speed zones on the approached to provincial cities/towns etc; and
  

• In construction speed zones to provide evidence of compliance with the speed zones and to encourage additional policing of speed zones to protect construction staff if speed compliance is not found.
  

Spot Speed Studies

Spot speed studies can be readily undertaken using our Laser Technologies LTI 20/20 Laser Speed Gun. This type of study involves an observer being located on the section of road in question and then covertly monitoring a sample of the traffic using the road. The sample required to produce a statistically reliable result can be quite small depending on the free speed of the traffic being monitored. The table below proves an indication of typical sample sizes required.

Copyright 2011 - Traffic and Parking Surveys Pty Ltd

The results of the monitoring are then plotted up to produce a cumulative distribution of speeds. An example of a typical output is shown below. Statistics such as mean speed, 85th%ile speed and the number of vehicles that comprise the sample are noted.

Automatic Classifier/Speed Surveys

Pneumatic tube classifiers can be installed to allow traffic speeds to be monitored over an extended period. This type of surveys allows speeds to be recorded 24 hours a day over an extended period.

Key statistics can be calculated including:

• Mean speeds by time of day;
  

• 85th%ile speeds for the whole sample and also for defined times of day;
  

• The classification of the vehicles measured.
  

These surveys are not covert as they require the installation of pneumatic tubes across the lanes being monitored.

Side-Fire Radar

Our Smartsensor Trailer can be installed clear of the road to monitor up to 10 lanes of traffic simultaneously. The Smartsensor must be installed at least 1.8 metres from the nearest traffic lane being monitored but can be installed up to about 15 meters from the nearest lane. The range of the Smartsensor is up to 70 metres.

Consequently the Smartsensor Trailer can be installed without the need to install tubes across the road and can, if the room is available, be installed away from the road where it is unlikely to have any impact on traffic operation and also clear of the traffic movements meaning that there is no need for traffic management to deploy the device.

The Smartsensor can be configured to operate 24 hours a day storing data in user defined intervals, classify vehicles counted in up to 8 user defined vehicle length bins, and classify vehicle speeds observed in the interval into up to 15 user defined speed bins. Additional statistics compiled include average speed of the vehicle observed in each interval and 85th%ile speed in each interval.

The Smartsensor is thus extremely useful in monitoring vehicle speeds in construction zones and elsewhere where the large traffic volumes make the installation of pneumatic tubes across the traffic lanes problematic.

Ph. 9874 7834