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When putting out the triangles, hold them between yourself and the oncoming traffic for your own safety. (So other drivers can see you.) 

Use Your Horn When Needed.  your horn can let others know you’re there. it can help to avoid a crash. Use your horn when needed. However, it can startle others and could be dangerous when used unnecessarily. 

## 2.6 – Controlling Speed 

Driving too fast is a major cause of fatal crashes. You must adjust your speed depending on driving conditions. These include traction, curves, visibility, traffic and hills. 

## 2.6.1 – Stopping Distance 

perception Distance + reaction Distance + Braking Distance = Total Stopping Distance 

Perception distance.  The distance your vehicle travels, in ideal conditions; from the time your eyes see a hazard until your brain recognizes it. Keep in mind certain mental and physical conditions can affect your perception distance. it can be affected greatly depending on visibility and the hazard itself. The average perception time for an alert driver is 1¾ seconds. At 55 mph this accounts for 142 feet traveled. 

Reaction distance. The distance you will continue to travel, in ideal conditions; before you physically hit the brakes, in response to a hazard seen ahead. The average driver has a reaction time of ¾ second to 1 second. At 55 mph this accounts for 61 feet traveled. 

Braking distance. The distance your vehicle will travel, in ideal conditions; while you are braking. At 55 mph on dry pavement with good brakes, it can take about 216 feet. 

Total stopping distance. The total minimum distance your vehicle has traveled, in ideal conditions; with everything considered, including perception distance, reaction distance and braking distance, until you can bring your vehicle to a complete stop. At 55 mph, your vehicle will travel a minimum of 419 feet. 

## The effect of Speed on Stopping Distance. 

The faster you drive, the greater the impact or striking power of your vehicle. When you double your speed from 20 to 40 mph the impact is 4 times greater. The braking distance is also 4 times longer. Triple the speed from 20 to 60 mph and the impact and braking distance is 9 times greater. At 60 mph, your stopping distance is greater than the length of a football field. Increase the speed to 80 

mph and the impact and braking distance are 16 times greater than at 20 mph. high speeds greatly increase the severity of crashes and stopping distances. By slowing down, you can reduce braking distance. 

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The effect of Vehicle Weight on Stopping Distance. The heavier the vehicle, the more work the brakes must do to stop it, and the more heat they absorb. But the brakes, tires, springs, and shock absorbers on heavy vehicles are designed to work best when the vehicle is fully loaded. Empty trucks require greater stopping distances because an empty vehicle has less traction. 

## 2.6.2 – Matching Speed to the Road Surface 

you can’t steer or brake a vehicle unless you have traction. Traction is friction between the tires and the road. There are some road conditions that reduce traction and call for lower speeds. 

Slippery Surfaces. It will take longer to stop, and it will be harder to turn without skidding, when the road is slippery. Wet roads can double stopping distance. you must drive slower to be able to stop in the same distance as on a dry road. reduce speed by about one-third (e.g., slow from 55 to about 35 mph) on a wet road. On packed snow, reduce speed by a half, or more. If the surface is icy, reduce speed to a crawl and stop driving as soon as you can safely do so. 

Identifying Slippery Surfaces. Sometimes it’s hard to know if the road is slippery. here are some signs of slippery roads: 

