CDL Driving Safely: Key Terms

Defect: A weak point or imperfection.

Manual Transmission: Made up of a system of interlocking gear wheels and a lever that lets the driver change the gears manually.

Automatic Transmission: System that changes gears automatically.

Engine speed: Drivers should study the driver’s manual to learn the RPM range you should be operating in.

Retarders: Used to help slow a vehicle which helps to limit use of brakes.

Convex Mirror: Reflective surface that curves outwards.

Divided Highway: Road with a median strip between the traffic in opposite directions.

Perception Distance: Distance your vehicle travels from the time your eyes see something until your brain registers it.

Reaction Distance: Distance you travel before the driver hits the brakes.

Braking Distance: Distance your vehicle travels while you are braking.

Stopping Distance: Perception distance + reaction distance + braking distance.

Black Ice: Thin sheet of ice. So thin that the driver can’t see the ice on the road.

Hydroplaning: When a vehicle slides uncontrollably on a wet surface.

Tailgaters: When a vehicle is driving to close behind another vehicle.

Road Rage: Anger that is the result of frustration while driving.

Tire chains: Chains that can be fitted on tires that help provide maximum traction in snowy or icy conditions.

Gates: Many railroad crossings have gates. These gates usually have flashing red lights and bells.