You’ve probably noticed the raised, bumpy patterns where the sidewalk ends. You might also have wondered why they are there in the first place. For traction? Durability?
Turns out there’s a very good reason, but it’s not what you may think it is.
Those blister-like bumps, also known as “truncated domes and detectible warning pavers,” are a part of “tactile paving” (meaning: paving that can be felt). It helps the visually impaired detect when they are about to leave the sidewalk and enter the street. They can feel the change in texture on the ground below them, and know to stop before proceeding to cross the street.
For the visually impaired with some vision, the bright yellow or red coloring on those sidewalk bumps also helps to alert them that the sidewalk is coming to an end.
Depending on where you are in the U.S. or other countries, you’ll find different tactile paving patterns.
British video producer Tom Scott explains some of them in this helpful video.
Offset bump patterns show a train platform ahead. Oblong circles designate a street trolley or tram. Stripes across a path signal steps or other trip hazards ahead. And stripes following a path guide someone on a safe walkway. Pavement bumps can also show a pedestrian versus a bike path.
Tactile paving first showed up in Japan in the late 1960s. And Japan still leads the way in accessibility options like in the subway below.
In Australia, they’re starting to install lighted street patterns to better signal the visually impaired (or plain oblivious). Because, to the point made in the video above, a small portion of those who are visually impaired are 100 percent blind, which is why it’s important to make tactile indicators as visible as possible for those with limited eyesight.
In some places, tactile pavers match the sidewalk color or are a more subdued color, making them less visible to those with eyesight issues. Sometimes the braille-like pathways aren’t set up clearly or safely.
But when those bumpy patterns are used correctly, they allow for a more accessible and safe street layout. That’s important when “there are tons of metal speeding past you,” as the video host Tom Scott says.