The length of time it takes a driver to identify a situation is called perception time. Perception time depends on visibility, the driver’s physical condition, and the road situation. Effectively scanning the road ahead will shorten your required perception time.
You can improve your ability to gather information by grouping like items into four basic categories discussed in the next slides.
1. Signs, Signals, and Roadway Markings
These items provide for the orderly movement of traffic. They help you make safe driving decisions by informing you of the condition of the road ahead of you.
2. The Highway
Look for objects on the road and in the area bordering the road that could possibly cause a collision. If there is a problem ahead, look for another path you can take to avoid a hazardous situation.
3. Motor-powered Vehicles
It can be difficult to gather good information about other motor-powered vehicles. Cars, motorcycles, trucks, and buses all handle and react differently to road conditions. Watch out for other drivers who do not have full control of their vehicles because of excessive speed or unnecessary lane changes. Adjust your speed and position to protect yourself against their possible actions. Remember that some drivers are less predictable than others.
4. Non-Motorized Highway Users
Pedestrians, bicycles, and animals belong to this group. They are the most vulnerable users of the highways and should be watched carefully whenever they come near a roadway.