What is the first phase of a vehicle collision?

The first phase of a vehicle collision is vehicle deceleration. This occurs when the vehicle comes into contact with another object or surface, which causes an immediate reduction in its speed. During this phase, the kinetic energy of the moving vehicle is transferred to the object it collides with, and the force of the impact begins to affect not just the vehicle but also its occupants.

Understanding this phase is crucial in emergency medical responses, as it sets the stage for subsequent events such as occupant deceleration and potential injuries. The vehicle's rapid deceleration initiates a series of secondary effects, including the movement of passengers within the car and the potential for internal injuries to occur as the body continues to move forward even after the vehicle itself has stopped. Recognizing that vehicle deceleration is the initial phase helps paramedics assess the situation appropriately and anticipate the types of injuries they may encounter in injured occupants.