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Thursday, February 26, 2009

When The Speed Limit Is Too Fast

Some drivers, after receiving a speeding ticket, complain that the speed limits are unreasonable and impossible to obey, while others go even further to claim that the speed laws are just a scheme concocted by the government to make money. The truth is that, for the most part, speed limits are set by traffic engineers to move the greatest amount of traffic at the highest safest speed. If that weren't the case, traffic gridlock would be even worse than it is.

Several different factors go into setting speed limits; the size and condition of the road, the amount of traffic the road is expected to carry, and things that adjoin the road such as schools or shopping centers. Speed limits are always set for ideal conditions. Speed limits can't take extraordinary conditions such as rain, snow, ice, or fog into account and it is these types of conditions that get drivers into a lot of trouble.

In November 2007 a foggy California highway became the scene of a massive pile up involving 108 vehicles and 18 big rigs resulting in two deaths. State authorities blamed excessive speed in foggy conditions for the pile-up.

Drivers tend to take the speed limit as gospel, often forgetting the other factors that go into determining what a safe speed should be. The posted speed limit doesn't mean that it is the safe limit. Drivers should travel at a speed lower than the posted speed limit when:

  • Visibility is limited - Many drivers don't realize just how much ground their vehicle is covering at high speeds. A car traveling at 60 mph is covering almost 90 feet per second. At that speed it takes up to 300 feet to bring a car to a complete stop. At 60 mph, if you can't see more than 300 feet ahead, you are driving too fast for conditions. Your speed should be set so that your vehicle can be brought to a stop within your sight distance or the distance covered by your headlights. Higher speeds mean that, by the time you see a hazard ahead and react to it, it is too late to stop in time to avoid a crash. Visibility is limited at night, in fog, snow, and when the sun is rising or setting in front of your vehicle. Dark country roads are the most dangerous of all roads. Many of the deaths on these types of roads happen when the driver is over-driving their headlights, encounter a curve and are unable to keep their car on the road.
  • Rain - The roads are most slippery just after the rain starts. Accumulated oil and grease on the road rises above the thin film of water creating an oil slick that can cause you to lose control. The rain will eventually wash the oil off the road but that takes time.
  • Standing water - Water standing on the road can be too deep for your tire treads to effectively squeeze out the water. As a result, your car's tires can rise up on top of the water and "hydroplane" across the surface of the water like water skis. Hydroplaning can start at speeds as low as 35 mph and becomes most dangerous at speeds of 55 mph or higher. Slow down when you encounter standing water on the road.
  • Snow and ice - Snow and ice are particularly treacherous. Packed snow can turn into ice. Ice accumulated on the road when the temperature is hovering right around the freezing mark can turn slushy and becomes especially treacherous. Most experts say that speed should be cut by half when traveling on packed snow or ice. Remember that bridges with freezing temperatures both above and below the surface freeze first.

    Remember, even if you are traveling at or below the speed limit, you can still get a ticket for driving too fast for conditions.

    Learn more by visiting's Dangers of Speeding course online.

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