Pavement Markings—Wet Retroreflectivity Standards

Pavement markings need to be visible to drivers both day and night and in adverse weather conditions such as rain. Markings in good condition typically provide adequate delineation under dry nighttime conditions, but performance is generally reduced in wet-night conditions. Wet reflective pavement markings can provide improved visibility in wet-night conditions. This research project identifies continuous wet retroreflectivity levels to include in Minnesota Department of Transportation (MnDOT) standards based on a comprehensive review of past research, an analysis of available data sources, and a human factors study. The human factors study included 43 participants who evaluate the visual performance of pavement markings with varying levels of retroreflectivity, color, and width in a simulated rain condition. The results indicate that a minimum maintained continuous wet retroreflectivity level of 50 millicandelas per meter squared per lux (mcd/m²/lux) will provide adequate visibility to most drivers. A new install value of 200 mcd/m²/lux is recommended. The new install value is based on anticipated continuous wet retroreflectivity degradation using literature and MnDOT-supplied continuous wet retroreflectivity degradation levels, a desired four-year service life, and the recommended minimum maintained value. These recommendations are not marking width or color dependent.

• Record URL:
  http://mndot.gov/research/reports/2020/202009.pdf
• Corporate Authors:

  Texas A&M Transportation Institute

  Texas A&M University System
  3135 TAMU
  College Station, TX  United States  77843-3135

  Minnesota Department of Transportation

  Office of Research & Innovation
  395 John Ireland Boulevard, MS 330
  St. Paul, MN  United States  55155-1899

  Minnesota Department of Transportation

  Local Road Research Board, 408 Transportation Building
  St Paul, MN  United States  55155
• Authors:
  • Pike, Adam
  • Barrette, Timothy
• Publication Date: 2020-3

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Figures; Photos; References; Tables;
• Pagination: 100p

Subject/Index Terms

• TRT Terms: Drivers; Human factors; Night; Recommendations; Retroreflectivity; Road markings; Standards; Visibility; Wet weather
• Geographic Terms: Minnesota
• Subject Areas: Design; Highways; Pavements;

Filing Info

• Accession Number: 01743401
• Record Type: Publication
• Report/Paper Numbers: MN 2020-09
• Contract Numbers: (c) 1003324 (wo) 1
• Files: TRIS, ATRI, STATEDOT
• Created Date: Jun 19 2020 2:32PM