The three collisions in a crash

When a crash occurs, a car occupant without a seat-belt will continue to move at the same speed at which the vehicle was travelling before the collision and will be catapulted forward into the structure of the vehicle – most likely into the steering wheel if they are driving, or into the back of the front seats if they are rear seat passengers.

There are three collisions that occur in every crash where a person isn’t wearing a seat-belt. The first collision involves the vehicle and another object, e.g. another vehicle, tree, signpost, ditch or or animal. The second collision occurs between the unbelted person and the vehicle interior, e.g. the driver hits his chest on the steering wheel or his head on the window. Finally, the third collision occurs when the internal organs of the body hit the chest wall or the skeleton. It is the second collision that is most responsible for injuries, and can be reduced significantly by the use of seat-belts and child restraints. The most serious injuries in a car crash are to the head, followed by the chest and the abdomen.

Seat-belts to the rescue

The use of seat-belts and child restraints is one of the most important actions that can be taken to prevent serious injury in a car  crash. While seat-belts and child restraints do not prevent crashes from taking place, they play a major role in reducing the severity of injury to vehicle occupants involved in a collision. An occupant’s chance of survival increases dramatically when appropriately restrained.

Since the 1960s studies  throughout the world have shown that seat-belts save lives.  A review of research on the effectiveness of seat-belts found that their use reduces the probability of being killed by 40–50% for drivers and front seat passengers and by about 25% for passengers in rear seats. The impact on serious injuries is almost as great, while the effect on slight injuries is smaller at 20–30%.