Tactile paving

Tactile paving (also called truncated domes, detectable warnings, Tactile Ground Surface Indicators, detectable warning surfaces) is a system of textured ground surface indicator found on footpaths, stairs and train station platforms to assist pedestrians who are blind or visually impaired.

Tactile warnings provide a distinctive surface pattern of truncated domes, cones or bars detectable by long cane or underfoot which are used to alert the visually impaired of approaching streets and hazardous surface or grade changes. There is a disagreement in the design and user community as to whether installing this aid inside buildings may cause a tripping hazard.

Originally instituted at pedestrian crossings and other hazardous road situations by Japan, the United Kingdom and Australia, the United States picked up the standard in the early 1990s, after passage of the Americans with Disabilities Act (ADA). Canada started incorporating them into transportation first in the 1990s, and then added them to other aspects of the built environment in the early 2000s.

The original tactile paving was developed by Seiichi Miyake in 1965. The paving was first introduced in a street in Okayama city, Japan, in 1967. Its use gradually spread in Japan and then around the world.

Today yellow tactile pavings are ubiquitous throughout Japan. For aesthetic reasons, for example in front of hotels, the colour of the paving can change to reflect the colour of the pavement or stone floor. Sometimes the paving contours are produced with steel stripes and dots.

The tactile tiles spread rapidly via their adoption at Japan National Railways (later known as Japan Railway). The system was formally named "Hazard Guide for the Visually Impaired" (視覚障害者誘導用) in 1985. It's modern form can be classified into two types. One has small, round bumps upon the surface of the block, which are felt through a sole. The second type of a block is a directional aid. Long and slender bumps are installed in the surface.

However, many types have been manufactured as an experiment and installed. This has resulted in a situation which may be confusing for both the visually impaired and for the elderly. Usually the color of a tile is used to check the proper direction. If the color is not clear, there may be confusion. This has led to standardisation of the system throughout Japan.

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