Traffic Safety Terms

Absolute Speed Limit The maximum or minimum posted speed which one may drive under normal conditions.

Actual Physical Control A person can be charged with “DUI” of alcohol or other drugs if they have the ability to move their vehicle.

Advisory Speed Limit A speed limit that advises drivers that an adjusted speed is necessary for a short period of time.

Antilock Brakes ABS A braking system that is designed to keep a car’s wheels from locking when a driver brakes abruptly.

Basic Speed Law A law that states that a driver must drive at a speed that is reasonable for existing conditions.

Blind Spot An area outside a vehicle that is not visible to the driver in the rear or side-view mirrors

Blood-Alcohol Concentration BAC The percent of alcohol in a person’s blood.

Carbon Monoxide A highly poisonous gas that is given off by the burning of fossil fuel, it is odorless and colorless.

Centrifugal Force A natural law that tends to push a vehicle out of a curve and into a straight path.

Contrast Sensitivity The ability to see under difficult conditions such as glare from oncoming headlights, snow, rain, etc.

Disc Brake system A system where brake pads are pressed against a flat metal wheel.

Driving Under the Influence (DUI) Driving under the influence of any mind altering substance.

Hand position Refers to the hand placement on the steering wheel while driving. Hand over hand and push-pull- feed are two examples.

Highway Hypnosis A drowsy state that may occur during long hours of driving.

Hydroplane To skim on top of a film of water.

Implied Consent Law A driver gives their consent to be tested for alcohol. This consent is given in the state where you sign your license.

Over-driving One’s Headlights Driving so fast at night that the driver is unable to stop in the range of the headlights.

Peer influence Young adults are victims of the influence of bad habits rather than pressures from peers.

Reversible Traffic Lane A traffic lane where the flow of traffic may change during different times of the day.

SIPDE A five step driving process that enables drivers to process information in an organized way.

SIPDE Search Identify Predict Decide Execute

Smith System A set of five principles that help drivers operate safely and smoothly.

Space Margin Keeping a safe distance around all sides of your vehicle. 2 seconds following a vehicle.

Synergistic effects of combining 2 or more drugs. Combinations of 2 or more different kinds of drugs can multiply the impairment of a person as much as 10 times.

Threshold Braking A braking technique in which the driver firmly presses the brake pedal to a point just before the wheels lock.

Total Stopping Distance The distance covered by a vehicle from the perception of conflict to the moment that the vehicle comes to a stop.

Visual Acuity A driver’s ability to see clearly under normal conditions. Examples of things that affect this are alcohol, drugs, fatigue, poor weather.

Velocitizing The sensation of moving more slowly than one actually is. It is a result of driving fast speeds for long period of time.