Here’s the purpose of those sidewalk bumps
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. No, it’s not for traction in bad weather. How about durability? That would be a good guess. But, even though you could consider durability a bonus feature, that is not the function, either.
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 — paving that can be felt. It helps visually impaired pedestrians detect when they are about to leave the sidewalk and enter the street.
These ground indicators are also sometimes known as Braille paving. These textured tiles make it easier for people to feel changes in patterns and textures. These changes signal changes in a path, including a curb or a change in direction.
They can feel the change in texture on the ground below them and know to stop before proceeding to cross the street. In this video, you can see how a Braille pathway can make a difference in getting around for someone who is visually impaired.
For people who are visually impaired but still have partial sight, 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.
What Do The Patterns Mean?
OK, so there are different bumps and patterns. But what do they all mean? Just as in the Braille language, each type of pattern has a significant meaning to the visually impaired.
Here’s a look at a few of the different patterns you’ll see out on the sidewalks and roadways.
1. Offset dots
This pattern, with dots positioned in diagonal lines, indicates a train track or other ledge ahead.
2. Lozenge-shaped bumps
Oblong or lozenge-shaped bumps indicate that you’re approaching the tracks of a street trolley, tram or other street-level transportation. So, these shaped-tiles help keep visually impaired people from wandering off platforms and sidewalks when using public transportation. These bumps save people’s lives.
3. Stripes across a path
Stripes that run across a path signal steps or other trip hazards ahead.
You’ll commonly find these before a staircase, for example.
4. Stripes along a path
Stripes that follow a path indicate a safe path.
Those who are visually impaired know to follow the stripes in order to steer clear of obstacles along the way.
Tactile paving first showed up in Japan in the late 1960s.
And Japan still leads the way in accessibility options, like in the subway, shown below.
China has also installed “blind lanes” on many of their sidewalks to assist those who are visually impaired. In fact, in 2001 the China’s central government mandated the construction of these pathways across the country. This included some of the most popular tourist areas such as Beijing and the Great Wall of China.
Here in the U.S., some say there’s still not enough accessibility despite the Americans with Disabilities Act passing back in 1990.
In some countries, they are starting to install lighted street patterns to better signal paths, because not everyone with a visual impairment is 100% blind. Making tactile indicators as visible as possible is helpful 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, though.
But when those bumpy patterns are used correctly, they allow for a more accessible and safe street layout. It can also mean a greater level of independence for people who want to get out in the community but struggle because of their vision.