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Human Factors Guidelines for Road Systems - Collection C: Chapters 16, 17, 18, 19, 20, 22 (Tutorials 4, 5, 6), 23 (Updated), 24, 25, 26 (Updated) (2010) / Chapter Skim
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Presentation to Maximize Visibility and Legibility
Pages 39-40

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From page 39...
... Additional recommendations for designing messages within the limitations imposed by CMS technologies, including guidelines for contrast ratio, luminance, character spacing, and resolution are provided below. Design Guidelines CMS Guideline Value Characteristic Contrast Ratio Optimal contrast ratio range = 8-12 (light-emitting where: CMS)
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From page 40...
... , reduce the brightness of the LED, thereby decreasing the contrast and making CMS messages difficult to read. Cross References Key Components of Sight Distance, 5-2 Sign Design to Improve Legibility, 18-4 Composing a Message to Maximize Comprehension, 19-8 Key References 1.
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  • flip disk
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  • ratio range
  • expert judgment

  • character spacing
  • ranges based
  • effective variable
  • thereby decreasing
  • cms standards

  • sign operation
  • issues appropriate
  • including guidelines
  • viewing comfort
  • references key

  • improve legibility
  • transportation institute
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  • advanced traveler


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