TRAFFIC DETECTOR SELECTION PROCEDURE (GUIDELINE DRAFT)

Traffic detection systems provide high quality real time and historical traffic data for a variety of traffic applications. Inductive loops, though they are the most widely deployed detector technology, have some limitations. They disrupt traffic flow during installation and maintenance, fail at a high rate under particular conditions, and are inflexible. Professionals are seeking alternative technologies to replace inductive loops. A large number of traffic detector devices with different operation theories are currently available on the market. Manufacturers are constantly improving detector performance and capabilities. No single detector device is best for all applications. Each has its limitations, specializations, and individual capabilities. Because such a diversity of detector technologies and devices exists, it may be problematic to select the optimal detector technology and particular device to meet specific project requirements. To a large extent, successful application of detector technologies depends on proper device selection. This guideline provides a systematic method for selecting detectors for permanent applications. The selection method considers many factors, including data type, data accuracy (within different environmental and traffic conditions), ease of installation and calibration, cost, reliability, and maintenance. A variety of detector technologies and devices are compared using these factors in order to help the user choose the best technology and device for his or her purposes. This guideline provides comparison matrixes for detector technologies and for specific detector devices. The technology matrixes provide general information about each detector technology, and the device matrixes offer specific information regarding each particular detector device. The matrixes need to be continuously updated to reflect new changes in the detector field.