Designed to help the blind and visually impaired navigate cities, tactile paving units are like braille for pavements. These raised bumps and ridges help guide people down sidewalks and across intersections. In many cases these work quite well, but in some places they have been deployed in less-successful ways (to put it mildly).
Tactile paving was first developed in Japan before spreading to other nations around the world, including Australia, Canada, the United Kingdom and the United States. Other countries, like China, have started using them more recently and with mixed results.
In most instances, raised ridges denote pathways (longer stretches between stops and changes). Raised domes, meanwhile, are used to indicate a stop or change (e.g. the presence of an intersection or edge or a shift in direction). Users register the different types of tactile signals with canes or their feet and respond accordingly. In China, however, these cues are less reliable — below are a few milder failures to start with:
When the government passed a law in 2001 requiring “blind lanes” to be built along major streets, compliance was inconsistent. The resulting implementations span a spectrum from annoying to downright dangerous. In some places, the textured tiles have simply been misused as decorative touches, defeating their critical purpose. In others, angled tile patterns force blind lanes to zig and zag their way down a street, which would surely be a bit frustrating to users. […]