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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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Determining Appropriate Message Length
Pages 41-42

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From page 41...
... NEW YORK unit consists of message read at speeds less What should they do? USE I-280 EAST 1 to 4 words than 35 mi/h Length: Use no more than: Number of words Eight words per message for or characters in a drivers at high speeds message, (based on the required reading excluding time of 1 s per four- to eight prepositions character word, excluding prepositions, or 2 s per Acceptable message length because the preposition "to" does information unit, whichever is not count.
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From page 42...
... Cross References Key Components of Sight Distance, 5-2 Presentation to Maximize Visibility and Legibility, 19-4 Changeable Message Signs, 13-6 Composing a Message to Maximize Comprehension, 19-8 When to Use Changeable Message Signs, 19-2 Displaying Messages with Dynamic Characteristics, 19-10 Key References 1. Dudek, C.L.
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Key Terms

  • message length
  • changeable message
  • message signs
  • legibility distance
  • compatible information

  • required viewing
  • viewing distance
  • information unit
  • appropriate absolute
  • approximate legibility

  • units included
  • message sign
  • includes information
  • reading time
  • message includes

  • increases reading
  • message intent
  • information media
  • minimum phase
  • appropriate abbreviations

  • phase display
  • reading signs
  • single information
  • legibility zone
  • driver workload

  • matrix sign
  • absolute message
  • unimportant information
  • units contained
  • acceptable message


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