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3.0 Signing, Markings and Channelization

3.6.5 Recommended Guidelines

CMS Design Issues

CMS Guideline Development:

Guideline CMS Guideline 1
Title CMS Technology
Text CMS using a LED technology should be used for all new installations.
Commentary When budget is a significant consideration and if visibility concerns can be adequately addressed for a particular installation, a CMS using a mechanical technology should be considered to satisfy a message variability requirement.


Guideline CMS Guideline 2
Title CMS Visibility
Text The CMS should be visible for a distance at least equal to the depth of the queue zone plus an additional 40 - 50% approach factor. The minimum letter height should be 10.6 inches. Word messages should be created using all Upper Case letters.
Commentary None


Guideline CMS Guideline 3
Title CMS Brightness
Text CMS using a light based technology should be capable of a minimum of three levels of brightness that are based on data inputs from a minimum of three photocells.
Commentary Fog conditions may severely impact visibility regardless of the brightness level.


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