Tactile Walking Surface Indicators To Aid Wayfinding For Visually Impaired Travelers In Multimodal Travel

Many countries make extensive use of tactile walking surface indicators (TWSIs) and may require that they are according to the adopted standards to aid wayfinding for travelers who are visually impaired, including those who are blind or who have low vision. TWSIs are typically made up of attention fields (truncated domes—referred to in the United States as detectable warning surfaces [DWSs], and guiding patterns (raised parallel bars). The truncated domes and the guiding patterns are combined to define paths of travel in pedestrian areas, including public rights-of-way and multimodal transportation facilities. There is increasing recognition in the United States that tactile guiding patterns may be an effective solution to wayfinding problems for visually impaired travelers where there are insufficient cues in the built environment to enable effective wayfinding. Examples are rail and transit stations and hubs, intermodal terminals, plazas, irregular and confusing intersections such as roundabouts and channelized turn lanes, alternative intersections, shared streets, and parallel pedestrian/cycle paths at the same level. Consistency in cues for wayfinding is extremely important to travelers who are visually impaired in order for them to understand the messages of such cues and because they are unable to use many other cues available to travelers with unimpaired vision. TWSIs, including both attention patterns (DWSs) and guidance patterns (raised bars), are loosely standardized on the basis of then existing research and practice in ISO 23599: Assistive Products for Blind and Vision- Impaired persons—Tactile Walking Surface Indicators (2012). The only systematic use of TWSIs in the United States is detectable warning surfaces (DWSs), which are required at transit platform edges and curb ramps as well as other locations where there is no distinction in level between pedestrian and vehicular ways. Standards ensuring consistency for the surface texture and some consistency in the installation of DWSs in the United States are contained in the 2006 Standards for Transportation Facilities and the 2010 Americans with Disabilities Act Standards. Similar consistency is needed in the surface textures and installation of guiding patterns. A number of U.S. jurisdictions and transit authorities have begun to explore or install guiding patterns DWSs such as truncated domes where it has been determined that there are insufficient cues for wayfinding. These include Caltrans, Los Angeles METRO, BART, New York DOT, DC DOT, Seattle, Minneapolis, Cambridge, MA, Vancouver, BC, and Alexandria, VA. While most of these installations are raised bar surfaces, there is great variation in the installation and materials, including the width and height (detectability) of the guiding pattern and where it is located. The objective of this research is to produce guidance for transportation planners and engineers, based on research that will provide for consistency in the design and installation of TWSIs in multimodal transportation in the United States.


  • English


  • Status: Proposed
  • Funding: $215740
  • Contract Numbers:

    Project B-46

  • Sponsor Organizations:

    Transit Cooperative Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC    20001

    Federal Transit Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Project Managers:

    Parker, Stephan

  • Start Date: 20180501
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01667910
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project B-46
  • Files: TRB, RiP
  • Created Date: Apr 30 2018 3:14PM