California Oregon Advanced Transportation Systems (COATS) Update - September 1st, 2011


UPDATE: Thursday, September 1st, 2011

Permanent pole-mounted style speed sign unit. Trailer style speed sign unit.

Permanent Pole-mounted Unit
Photo by Ian Turnbull

Trailer Unit
Photo by David Veneziano

The Radar Speed Trailer deployment warrants project was recently brought to a close with the completion of the final report and a project presentation at the 2011 National Rural ITS Conference (NRITS).

Over the course of the project, two levels of guidance were developed: general guidance and location-specific guidance. This guidance was based on a review of maintenance practices and the evaluation of the effectiveness of such signage in applications similar to those intended for use in California. General guidance warrants applied to cases where a radar speed sign may be used to address excessive mean speed and 85th percentile speed issues, ADT levels, speed limit compliance issues, accident history, pedestrian presence, and existing posted speed limits. Location-specific guidance applied to the use of radar speed signs in school and park zones, work zones, and general street locations such as transition zones, curve warning sign locations, and signal approaches. To a large extent, these cover a wide range of the deployment settings already pursued in California. Where the guidance is likely to differ from current practice is in the call for different thresholds to be met before deploying signage.

In addition to developing guidance for the use of radar speed trailers, specifications were developed for such equipment to guide practitioners in future purchases and deployments. The specifications developed related to the physical and functional specifications for both permanent post-mounted radar speed signs (and portable post-mounted signs) as well as trailer-based radar speed signs. The specifications represent a minimum that should be employed by agencies when considering a radar speed sign purchase. They detail all aspects (electrical, dimensional, luminary, performance, etc.) of radar speed signs (and trailers for mobile units), providing purchasers who may not be familiar with such devices with specific parameters to meet in procurement. Applying these specifications would help in improving the uniformity and standardization of the equipment procured and deployments pursued by agencies.

To review the Effective Deployment of Radar Speed Signs final report click here or go to the COATS Phase 4 project Documents page.

At the recent NRITS conference, David Veneziano presented Development of Radar Speed Sign Warrants. Click here to review the presentation or go to the COATS Phase 4 project Documents page.

It should be noted that Radar Speed Sign devices are known by a number of different names including mobile roadside speedometers, speed trailers, dynamic speed displays, speed displays, speed feedback signs, driver feedback signs, and speed monitoring displays. Regardless of the naming convention, each describes the same general device.