Almost Every Speed Limit Is Too Low
15th May 2019
“We all speed, yet months and months usually pass between us seeing a crash,” lieutenant Megge tells us when we call to discuss speed limits. “That tells me that most of us are adequate, safe, reasonable drivers. Speeding and traffic safety have a small correlation.”
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As most honest drivers would probably concede, this means that if the speed limit on a highway decreases from 65 mph to 55 mph, most drivers will not drive 10 mph slower. But for the majority of drivers, the opposite is also true. If a survey team increases the speed limit by 10 mph, the speed of traffic will not shoot up 10 mph. It will stay around the same. Years of observing traffic has shown engineers that as long as a cop car is not in sight, most people simply drive at whatever speed they like.
May 16th, 2019 at 15:04
At one time (pre-Nixon?) the accepted method was to open a stretch of highway, check how fast people drove, and set the speed limit at a rate 90% drove.
It works because the safest speed in most areas is the speed most of the vehicles are travelling. Passing or being passed is dangerous. Cruising along is much safer.