What are the three components of a collision?

• A. Pedestrian, Vehicle, Roadway
• B. Driver, Vehicle, Roadway
• C. Driver, Weather, Roadway
• D. Vehicle, Roadway, Traffic signals

Answer: (B)

Think of a collision as the result of how three elements come together: the driver, the vehicle, and the roadway. Each plays a key role in whether a safe outcome occurs.

The vehicle provides the physical mass, speed, and safety systems that determine how forceful a crash could be and how much protection is available. The driver brings perception, decision-making, and control; their attention, reaction time, and actions directly affect whether a dangerous situation is avoided or worsened. The roadway sets the environment—surface conditions, grade, lighting, weather impact, and design features—that influence grip, visibility, and how quickly a vehicle can stop or maneuver.

While other factors like pedestrians, weather, or traffic signals can influence outcomes, they aren’t the three foundational components that define a collision in this framework. Pedestrians are participants in some crashes, weather and signals are environmental factors, but the core system that explains most crashes centers on the interaction of driver, vehicle, and roadway.