SAN FRANCISCO (KGO) -- With school back in session, safe driving is more important than ever.
The California Office of Traffic Safety keeps track of crash data.
In 2016, in all Bay Area counties, there were nearly 12,000 speed-related crashes involving injury or death.
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Close to 3,400 of those involved a pedestrian. Almost 290 involved a kid under 15.
These were the five counties with the most speed-related crashes involving injury or death.
San Francisco is particularly unique because all but 14 of their 950 crashes involved pedestrians.
To take a closer look at these crashes, ABC7 News Reporter Cornell Barnard asked transportation experts to help us with a real-time experiment on just how long it takes your car to stop when you hit the brakes.
We asked John Knox White from the San Francisco Municipal Transportation Agency to help us with a real-time driving test.
The Cow Palace allowed us to use its parking lot to test braking distances in a simulated cross walk.
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We measured out a 30-foot braking distance, then got to work.
With this reporter behind the wheel, our first run was at 20 mph. A traffic cone in the center might be a person, or a bicyclist.
Stopping was not so easy. Then we took it up to 25 mph and hit the brakes.
On both runs, the cone wasn't harmed.
But then we increased our speed to 30 mph, not a safe speed for any school crosswalk. Watch what happens when I try to stop in time.
Our traffic cone wound up lodged under the car and I was a nervous wreck. Very scary.
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"People don't understand the difference between 25 and 30 mph... 30 is big -- you're twice as likely to kill somebody, " said Knox White.
The results were just as tragic when our assistant warned us to stop suddenly on the course.
In this unscientific test, the cone always bounced right back.
"I think it's important to remember we may have hit a cone but we're talking about human beings," Knox White added.
San Francisco is working to reduce pedestrian deaths, but experts say it all starts with un-distracted driving. Drive safely out there.
See more stories and videos about Building a Better Bay Area here.
Hit the brakes! ABC7 conducts real-time driving test
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