WINDHOEK – Majority of Namibians have some kind of aversion to the use of safety belts. They understand that the use of safety belts is to avoid a traffic fine and as much as one does not see the traffic officers on the road, its use is forgotten.
Only a handful understands the importance of safety belt. These include survivors of road crashes that have gained some serious respect for safety belts, as they experienced its uses first hand. Another school are the ones that owes their ‘second chance’ in life due to the wearing of safety belts at the time of their accidents.
Since we are just a few weeks away to the holidays, it is of utmost importance that we understand why we must wear safety belts.
The basic idea of a seatbelt is very simple: It keeps you from flying through the windshield or hurdling toward the dashboard when your car comes to an abrupt stop. But why would this happen in the first place? In short, because of inertia.
Inertia is an object’s tendency to keep moving until something else works against this motion. To put it another way, inertia is every object’s resistance to changing its speed and direction of travel. Things naturally want to keep going.
If a car is travelling at 120 kilometres per hour, inertia wants to keep it going 120 kilometres per hour in one direction. Air resistance and friction with the road are constantly slowing it down, but the engine’s power compensates for this energy loss.
Anything that is in the car, including the driver and passengers, has its own inertia, which is separate from the car’s inertia. The car accelerates riders to its speed. Imagine that you’re cruising at a steady 120 kilometres per hour. Your speed and the car’s speed are pretty much equal, so you feel like you and the car are moving as a single unit.
But if the car were to crash into a telephone pole, it would be obvious that your inertia and the car’s were absolutely independent. The force of the pole would bring the car to an abrupt stop, but your speed would remain the same. Without a seatbelt, you would either slam into the steering wheel at 120 kilometres per hour or go flying through the windshield at 120 kilometres per hour. Just as the pole slowed the car down, the dashboard, windshield or the road would slow you down by exerting a tremendous amount of force.
It is a given that no matter what happens in a crash, something would have to exert force on you to slow you down. But depending on where and how the force is applied, you might be killed instantly or you might walk away from the damage unscathed.
If you hit the windshield with your head, the stopping power is concentrated on one of the most vulnerable parts of your body. It also stops you very quickly, since the glass is a hard surface. This can easily kill or severely injure a person.
A seatbelt’s job is to spread the stopping force across sturdier parts of your body in order to minimise damage.
A typical seatbelt consists of a lap belt, which rests over your pelvis, and a shoulder belt, which extends across your chest. The two belt sections are tightly secured to the frame of the car in order to hold passengers in their seats.
When the belt is worn correctly, it will apply most of the stopping force to the rib cage and the pelvis, which are relatively sturdy parts of the body. Since the belts extend across a wide section of your body, the force isn’t concentrated in a small area, so it can’t do as much damage.
Additionally, the seatbelt webbing is made of more flexible material than the dashboard or windshield. It stretches a little bit, which means the stop isn’t quite so abrupt. The seatbelt shouldn’t give more than a little, however, or you might bang into the steering wheel or side window. Safe seatbelts will only let you shift forward slightly.
A car’s crumple zones do the real work of softening the blow. Crumple zones are areas in the front and rear of a car that collapse relatively easily. Instead of the entire car coming to an abrupt stop when it hits an obstacle, it absorbs some of the impact force by flattening, like an empty soda can. The car’s cabin is much sturdier, so it does not crumple around the passengers. It continues moving briefly, crushing the front of the car against the obstacle. Of course, crumple zones will only protect you if you move with the cab of the car – that is, if you are secured to the seat by your seatbelt.
Car seatbelts have the ability to extend and retract – you can lean forward easily while the belt stays fairly taut. But in a collision, the belt will suddenly tighten up and hold you in place.
Here are 6 facts how safety belts prevent injuries:
Prevent ejection: Passenger vehicles are designed to keep occupants inside the vehicle where they can be protected. People thrown from a vehicle are four times more likely to be killed than those who remain inside.
Contact the body at the strongest parts of its structure: For an older child and adult, these parts are the hips and shoulders. For an infant and young child, there is really no part strong enough, so the child restraint supports the entire body to avoid stress on any one part.
Spread forces over a wide area of the body putting less stress on any one part.
Allow the body to slowly ride down the crash: Vehicles are engineered to crush in a controlled manner. Vehicle crush zones help extend the time it takes the vehicle to slow down. Safety belts tightly secure the occupant to the vehicle so the person can take maximum advantage of the extended stopping time and distance afforded by the crushing front end.
Protect the head and spinal cord: A shoulder belt helps to keep the head and upper body away from the hard interior surfaces of the vehicle. Correct fit is very important.
Keeps occupants of the vehicle from striking each other: Unbuckled rear seat occupants can injure buckled up front seat occupants as well as themselves when they are thrown around or out of the car in a crash.
By Felix Tjozongoro