- In rain, water, and fog – Speed should be reduced by about a third. For example, if the speed limit is 55 mph, drive 35 mph.
- On packed snow – Reduce speed by half or more.
- When there is ice on the road – Don’t drive. Slow to a crawl and stop as soon as it is safe to do so.
Truck driving requires constant consideration of a number of things to make sure the truck, its cargo, and the other drivers stay safe while on the road. One consideration that truck drivers must always be thinking about is stopping distance, which, as every experienced truck driver knows, is a lot more complex than just speed and response time. There are five main external factors that can affect a truck’s stopping distance and knowing what they are and how to respond to them is crucial to maintaining control and avoiding accidents. 1. Traction Traction is the resistance between a tire and the ground that allows the tire to exert enough force on the road to change a truck’s direction or speed. This resistance is reduced when the road surface is slippery, decreasing the tire’s ability to exert the force necessary to control the truck. This loss in traction increases stopping distance, sometimes doubling the amount of time it takes a truck to stop when driving on wet roads. Since truck drivers cannot control road conditions and must still drive during less-than-ideal weather, they must adjust the one thing they can control—speed. Driving a truck at a lower speed can counteract the reduction in traction. The slickness of the road surface determines how much a truck driver should reduce their speed.