What’s Vision Zero, and how does it work? This video explains.

Traffic deaths are all too common on our streets. To curb them, DC and Montgomery County have followed the lead of cities from around the world in adopting a program called Vision Zero. This video explains how it works:

The premise of Vision Zero is that human error causes most traffic collisions and that if you eliminate the chances for those errors to be made, you'll drive deaths down. Consider, for example, a street that sees a lot of pedestrians but doesn't have sidewalks: if you make the speed limit only six miles per hour and install speed bumps, it's very unlikely that a driver will hit someone at a speed high enough to kill them.

In more technical terms, Vision Zero takes a “systematic safety” approach to street design, which has five key principles:

• Establish maximum safe speeds for roads and keep cars separated from pedestrians and cyclists
• Make sure streets are safe relative to how people will use them daily
• Make streets predictable and simple
• Leep people from being able to break the law where it might be tempting
• Work to limit things that don't have to do with design but make roads unsafe, like texting while driving or driving drunk

The video looks at streets in the Netherlands, where safety has been a guiding principle behind street design for a few decades. Throughout the video, you'll see shots of Dutch streets full of separated bike lanes, clearly-marked crosswalks, and low car speeds. Though the Dutch refer to their approach as “sustainable safety,” its principles surely influenced engineers in Sweden, who invented Vision Zero in 1997.