The Transportation Research Board (TRB) Highway Traffic Monitoring Committee is a standing committee that was originally formed in 1985 as a Weigh-In-Motion Task Force and that developed into an ITS-oriented committee that studies all functions of traffic monitoring programs. In anticipation of the release of a new Transportation Research Circular, the committee surveyed the state of the practice, best practices, current issues, needs, and research gaps for topics covered in the Circular.
Quality assurance and quality control methods for collecting transportation data are common topics of concern for agencies. The TRB committee assembled a list of best practices for field device calibration.
The assembled list of best practices includes:
- Use intuitive database structures. Some agencies surveyed in the state-of-the-practice report have established computerized data collection and storage by the lane or travel direction of the identified vehicles.
- Keep up to date with data validation and verification. The report highlighted the practice of reviewing regular reports on data completeness, quality issues, and the status of each day's data.
- Determine the most effective method of procuring data. Some agencies reported paying for data, which, when properly sourced, can ensure that it is complete and of good quality, and eliminates the need for in-house staff to collect it.
- Make data available to your customers. Many agencies provide data online. In addition to expanding opportunities for the public, this practice can even be a benefit to the agency, as user downloads can encourage feedback and review to highlight errors or gaps in the data.
- Use visualizations to glean information. By geolocating data and layering it with other geographic information system (GIS) data, agencies may easily and intuitively improve their asset management systems.
- Calibrate your data. Volume data from HPMS, the Travel Monitoring Analysis System (TMAS), and the National Household Travel Survey (NHTS) afford opportunities to verify data quality and calibration and can ensure that reported values represent the actual vehicle mix traveling on the roadway network.