How Are the Speed Limits Created?January 24, 2013 | in Defensive Driving Tips
You know that speed limit sign that you have to follow religiously unless you want to risk an expensive traffic ticket? What if you found out it was created based around the opinion of one person. Okay, maybe not just one person, but a traffic engineer always gets the final say when a speed limit is being decided.
How exactly does it work?
Most states actually operate with the 85th percentile rule. Traffic studies are done on new roads, evaluating what speeds 85 percent of the people drive at. This rule works because most people will drive at a reasonable speed based on the conditions of that particular road. Yes, you will get your few people that always drive way too fast or way too slow, but most people naturally drive at a good pace. However, that is not the end of the equation.
What else is considered?
As mentioned above, a traffic engineer (or team of engineers) is always responsible for setting the final speed limit. They highly consider the 85th percentile rule, but they will also take into account additional details. Here are a few of the things that are also considered when speed limits are being established:
- The type of the road. Is the road straight or curved? Is it flat or does it have an incline or decline?
- Where is the road located? Is it in a residential area? Are there any intersections nearby that may require a sudden stop?
- What traffic control devices are nearby? Are there stoplights and stop signs that require vehicles to stop on a regular basis?
- How many accidents have occurred on this road? Could this be a sign slower speed limits might be necessary?
- How many vehicles use this road on a regular basis?
- How far ahead can a driver see on a clear day? Will they be able to see far enough to warrant faster speed limits?
After all of the above questions are answered, along with a study of what speed the majority of people currently drive on the road, a final speed limit is determined. Speed limits are not just random guesses as to how fast you should be driving. Contrarily, they are thoroughly evaluated figures to keep you moving at the safest speed possible. For more tips on safe driving visit DefensiveDriving.com.← Do All New Cars Come With XM Radio? | HOV Lanes: What You Need to Know →