Retroreflective Traffic Signal Backplates

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Improve visibility of traffic signals by adding retroreflective borders around them.

Description

Retroreflective borders on backplates added to traffic signals improve the visibility of the illuminated face of traffic signal in both day and nighttime conditions. This typically involves framing the signal with 1- to 3-inch-wide retroreflective border. This countermeasure is considered a low-cost method to enhance signals to account for human error, as well as increase visibility for both older and color vision deficient drivers. The backplates also provide additional visual cues during power-outages when the signals could be dark.

Safety Benefits

  • Improves visibility of the illuminated face of traffic signals.
  • Reduces risk of crashes caused by driver inattentiveness and poor visibility conditions such as at night, heavy fog, heavy precipitation, or strong backlighting. 

Street Types and Context

Applicable Street Types

All street types with signalized intersections

Primary User Groups

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Key Implementation Considerations

  • The addition of backplates with retroreflective borders should be considered to systematically improve safety at signalized intersections.
  • The design of the existing signal support structure must be considered to ensure that the design is sufficient to support the added wind load.
  • Corridors that are impacted by sun glare (east / west) may particularly benefit from back plate installation. 

Expected Crash Reduction

15% reduction in total crashes (Sayed et al., 2005).

Cost

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The addition of retroreflective signal backplates are relatively low cost when it is not necessary to purchase entirely new backplates. However, depending on the scale of the project, the price can vary if new signals and backplates are being purchased.

Timeline

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Varies, from months to three or more years, depending on accessibility of existing signals heads and structural limitations.

Application in Arlington 

Visit the Vision Zero Program Dashboard: Backplate to see where this tool has been implemented.

Vision Zero Dashboard

References

 

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