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Reexamination of Color Vision Standards, Part 3: Analysis of the Effects of Color Vision Deficiencies in Using ATC Displays

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Final rept.

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This report assesses the effect of color use in air traffic control ATC displays for users who have color vision deficiencies, denoted as color deficient CD. Color is extensively used in many ATC displays, yet the color vision standard used by the Federal Aviation Administration FAA allows certain types of CDs to enter the ATC workforce. Many guidelines for color use in visual displays state that color use should be accompanied by achromatic redundant cues to avoid misinterpretation by CD users. However, little has been documented in guidelines about the effect of redundant cues. Therefore, it is necessary to understand how CD personnel use color-coded information in displays and whether redundant cues are helpful. Previously, the authors collected data about color use in displays from many ATC facilities. They also developed computational algorithms that could assess the effects of color vision deficiencies on the performance of color-related ATC tasks. The algorithms compared the effectiveness of using color-coded information between observers with normal color vision and CDs. The algorithms also considered the effectiveness of redundant visual cues relative to colors. In this report, they applied the algorithms to six ATC displays to estimate their efficient use by CDs. The main findings included the following 1 critical color-coded information may not capture the attention of CDs in many applications 2 there are instances in which CDs may not reliably identify types of information that are encoded in colors and 3 in many instances color use makes text reading slower and less accurate for CDs. These results indicate that CDs may not be able to use color displays as efficiently as users with normal vision. In addition, the authors identified situations in which no redundant cues were used for task-critical color usages. Moreover, they estimated that most redundant cues were not as effective as color or were not effective at all for the given task.

Subject Categories:

  • Commercial and General Aviation
  • Anatomy and Physiology
  • Air Navigation and Guidance
  • Human Factors Engineering and Man Machine Systems

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