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A Tactile Guidestrip for Blind Pedestrians

Visually handicapped persons are taught to use the sound of traffic for guidance in aligning themselves properly at intersections. Traffic sounds are also used to indicate when to step off the curb and to maintain the direction of travel while crossing. This technique works satisfactorily at the majority of intersections, which cross at right angles. However, for those complex intersections with more than two streets, unusual crosswalks, diagonal crossings, or exceptionally wide streets, it is difficult to maintain proper direction while crossing, and a blind pedestrian might veer into oncoming traffic. In San Diego, an experimental tactile guidestrip has been installed to help visually handicapped pedestrians in crossing complicated intersections. The Public Works Department worked in close cooperation with staff from the Blind Recreation Center, the San Diego City Schools, and the Department of Rehabilitation to develop the mobility aid. The cooperative efforts were begun to solve a problem in the travel route of a mobility client of the Blind Recreation Center who was learning to travel from his home to his work downtown. One intersection was difficult to negotiate because of its diagonal configuration and constant traffic. The city's traffic engineer and the Public Works Department designed a four-inch wide strip of epoxy cement into which quarter-inch pea gravel was imbedded. The strip was placed in the crosswalk about eight feet from the parallel street to provide clearance from the parallel traffic (see Figure 1). The mobility student practiced crossing with the guidestrip. He approached the intersection, located the strip in the cross-