10-13-05 Planning Comm. Agenda - Laserfiche WebLink

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The report takes an extremely conservative approach as to message change interval, advising against the use of operations other than nearly instantaneous message changes. If such operations are permitted, the report suggests "that the figure commonly used as a measure of average glance duration, 0.3 second, be used here as a maximum permissible message change time limit." The report further advocates minimizing off-time between messages, where static message changes are used, stating that "[a]s this interval of off-time is lengthened, the difficulty of maintaining the continuity of attention and comprehension is increased." The conservative nature of the authors' position is reflected both in the report, and in over twenty years of practice since the report was issued. The report cites studies indicating that, in some situations, the use of electronic operations had a beneficial effect on traffic safety, by creating a more visually-stimulating environment along an otherwise mind-numbing segment of highway, helping to re-focus and sharpen the driver's attention to his or her surroundings. In over twenty years of experience, with numerous electronic signs nationwide utilizing the various operational capabilities for message change, there has been no significant degradation to highway safety reported. Many electronic signs used by highway departments now use a mode of transition between messages or message segments, such as traveling or scrolling. Drivers are apparently capable of attaching primacy to the visual information most critical to the driving task, with sign messages taking a secondary role. The report further expresses its limited focus upon interstate and federal aid primary highways. Noting the stimulating visual environment created by full- animation signage in places like Times Square, Las Vegas and Toronto's Eaton Centre, the authors of the report agreed that such signs added vitality and dimension to the urban core, but discouraged the use of animation alongside the highway. The report did not deal with the use of such signs, or their operational characteristics, on roadways between the extremes of the interstate highway and the urban core. In addition, animation has now been used on highway-oriented signs in many locations for years, with no reported adverse effect of traffic safety. r.~ ~, ~~ A3~ x~ ~" i ` b~1 lli!~ Ti \;`' ar.:) sum, the report acknowledged the appropriateness of full-animatio\ electronic signs within the urban core, but recommended that full-animation not be used along interstate and primary highways. It took a conservative position on operations of such signs along highways, advocating static message change sequences only, with no more than 0.3 seconds of message change interval or "off-time' between messages. The message changes on __ sequential segmented messages should be displayed such that a motorist can see and read the entire chain of message segments in a single pass. Messages should be permitted to change at "reasonable intervals." Such sig 27-