Radar speed displays have become the technology of choice for a growing number of law enforcement professionals looking to slow traffic. In a national survey of police officers, traffic engineers and corporate safety officials, the displays were identified as the single most effective traffic calming solution near schools, playgrounds and neighborhood streets. More than speed bumps, stop signs or even police with radar guns, radar speed displays were ranked as the preferred means of slowing speeders and keeping average driving speeds down in the long run.
A number of factors have led to the adoption of radar speed displays — from a growing base of statistical findings that prove their effectiveness, to advancements in the technology itself. As features, designs and technologies evolve, so does the disparity between various styles and brands. A review of these differences and a look at specific issues for consideration will help ensure that the right equipment is used.MUTCD compliance
If you are installing a traffic control device on a public street or highway, chances are the equipment must meet requirements of the MUTCD (Manual on Uniform Traffic Control Devices). The Federal Highway Administration's MUTCD sets the standards for size, shape, dimensions, content and color of displays for use on all federal roadways, and most states and municipalities have adopted the MUTCD standard.Alerts!
Radar speed displays are designed to communicate messages and alert speeding drivers in many different ways. The "Your Speed" message often remains static while the driver's actual speed is displayed when the car approaches, and some signs can be set to flash the actual speed number when the driver exceeds a predetermined limit. Others display a "Slow Down" message at a pre-set threshold.Scheduling
Pre-scheduling changes to the signs' functions can be a huge savings in time and cost. Signs that automatically change their posted speed limit take the guess work out of legal driving speeds in school zones, along carpool lanes and locations where the limit changes depending upon the time of day.
The scheduling capabilities of various electronic signs differ. Some may not have any scheduling capabilities, while others may allow multiple changes depending upon the time of day or day of the week. Features may allow scheduled speed limit changes, scheduled use of accessories such as flashers, scheduling speed limit thresholds (the speed that needs to be exceeded before the display switches to a message or turns off), or scheduled message changes.
Some radar speed displays allow users to collect data regarding traffic flow, such as the total number of cars using the street, average speeds at any given time of day, number of speeding cars, etc. This can provide the raw data needed to prove that an existing speeding problem exists, and validate the overall effectiveness of the display.
As valuable as advanced scheduling and data collection may be, engineers are finding that they often remain unused if signs are difficult to set, monitor or access. To address this, some manufacturers incorporate wireless connectivity options in their signs. Wireless options range from simple handheld devices that provide close-range connectivity to full cellular remote-office capabilities.
Handheld devices let users download collected data or change features from the comfort of their car. This has proven to be a significant improvement over models that require the manual manipulation of the sign itself. Instead of having to open up and access an interior control panel in order to collect data or set features, the wireless devices allow simple drive-up connectivity, download and scheduling.
Signs with remote office accessibility have recently been introduced onto the market. With this, city safety experts can use an office PC to monitor and control any number of signs from a single remote office location. The built-in cellular technology can synchronize multiple signs to ensure uniform operations.