Seat Ibiza: Why wear seat belts?

Seat Ibiza Owners Manual

Frontal collisions and the laws of physics

In the event of a frontal collision, a large amount of kinetic energy is generated.

Fig. 6 Vehicle about to hit a wall: the occupants are not wearing seatbelts

Fig. 7 The vehicle hits the wall: the occupants are not wearing seatbelts

It is easy to explain how the laws of physics work in the case of a head-on collision: When a vehicle starts moving ⇒ fig. 6 there is a certain amount of energy known as “kinetic energy”, both in the vehicle and in the occupants. The amount of “kinetic energy” depends on the speed of the vehicle and the weight of the vehicle and passengers. The higher the speed and the greater the weight, the more energy there is to be “released” in an accident. The most significant factor, however, is the speed of the vehicle. If the speed doubles from 25 km/h to 50 km/h, for example, the kinetic energy increases by a factor of four. Because the passengers in our example are not restrained by seat belts, the entire amount of kinetic energy has to be absorbed at the point of impact ⇒ fig. 7. Even at speeds of 30 km/h to 50 km/h, the forces acting on bodies in a collision can easily exceed one tonne (1,000 kg). At greater speed these forces are even higher.

Passengers not wearing seat belts are not “attached” to the vehicle. In a frontal collision they will continue to move forward at the speed their vehicle

was travelling just before the impact. This example applies not only to frontal accidents, but to all accidents and collisions.

The danger of not using the seat belt

Many people believe that the occupants can protect themselves with their hands in a minor collision, this is false.

Fig. 8 A driver not wearing a seat belt is thrown forward violently.

Fig. 9 The unbelted rear passenger is thrown forward violently, hitting the driver wearing a seat belt.

Even at low speeds the forces acting on the body in a collision are so great that it is not possible to brace oneself with one's hands. In a frontal collision, unbelted passengers are thrown forward and will make violent contact with the steering wheel, dashboard, windscreen or whatever else is in the way ⇒ fig. 8. The airbag system is not a substitute for the seat belts. When deployed, airbags provide only additional protection. All occupants (including the driver) must be wearing seat belts properly during the trip. This will reduce the risk of severe injuries in the event of an accident – regardless of whether an airbag is fitted for the seat. Note that airbags can be triggered only once. To achieve the best possible protection, the seat belt must always be worn properly so that you will be protected in accidents in which no airbag is deployed. It is also important for the rear passengers to wear seat belts properly, as they could otherwise be thrown forward violently in an accident. Rear passengers who do not use seat belts endanger not only themselves but also the front occupants ⇒ fig. 9.

Seat belts protect

Passengers not wearing seat belts risk severe injuries in the event of an accident.

Fig. 10 Driver wearing the seat belt properly: is secured by the belt in sharp braking

Properly worn seat belts hold the vehicle occupants in the correct sitting positions and substantially reduce the kinetic energy in the event of an accident. Seat belts also help to prevent uncontrolled movements that could lead to severe injuries. In addition, properly worn seat belts reduce the danger of being thrown from the car. Passengers wearing their seat belts correctly benefit greatly from the ability of the belts to absorb kinetic energy. The front crumple zones and other passive safety features (such as the airbag system) are also designed to absorb the kinetic energy generated in a collision. Taken together, all these features reduce the forces acting on the occupants and consequently the risk of injury.

Our examples describe frontal collisions. Of course, properly worn seat belts reduce substantially the risk of injury in all other types of accidents. This is

why it is so important to fasten seat belts before every trip, even when "just driving around the corner". Ensure that your passengers wear their seat belts as well. Accident statistics have shown properly worn seat belts to be an effective means of substantially reducing the risk of injury and improving the chances of survival in a serious accident. Furthermore, properly worn seat belts improve the protection provided by airbags in the event of an accident. For this reason, wearing a seat belt is required by law in most countries. Although your vehicle is equipped with airbags, the seat belts must be fastened and worn. The front airbags, for example, are only triggered in some frontal accidents. The front airbags will not be triggered during minor frontal collisions, minor side collisions, rear collisions, rolls or accidents in which the airbag trigger threshold in the control unit is not exceeded. Therefore, you should always wear your seat belt and ensure that your passengers have fastened their seat belts properly before you drive off!

Safety notes on using seat belts

If seat belts are used correctly, they can reduce the risk of injury in an accident.

– Always wear the seat belt as described in this booklet. – Ensure that the seat belts can be fastened at all times and are not damaged.

WARNING

If the seat belts are worn incorrectly or not at all, the risk of severe injuries increases. The optimal protection from seat belts can be achieved only if you use them properly.

• Fasten your seat belt before every trip - even when driving in town. That applies also to your front and rear passengers – danger of injury!

• The seat belt cannot offer its full protection if the belt web is not positioned correctly.

• Never allow two passengers (even children) to share the same seat belt.

• Keep both feet in the foot-well in front of your seat as long as the vehicle is in motion.

• Never unbuckle a seat belt while the vehicle is in motion. Risk of fatal injury.

• The belt webbing must never be twisted while it is being worn.

• The belt webbing should never lie on hard or fragile objects (such as glasses or pens, etc.) because this can cause injuries.

• Do not allow the seat belt to be damaged or jammed, or to rub on any sharp edges.

• Never wear the seat belt under the arm or in any other incorrect position.

• Loose, bulky clothing (such as an overcoat over a jacket) impairs the proper fit and function of the belts, reducing their capacity to protect.

• The slot in the seat belt buckle must not be blocked with paper or other objects, as this can prevent the latch plate from engaging securely.

• Never use seat belt clips, retaining rings or similar instruments to alter the position of the belt webbing.

• Frayed or torn seat belts or damage to the connections, belt retractors or parts of the buckle could cause severe injuries in the event of an accident. Therefore, you must check the condition of all seat belts at regular intervals.

• Seat belts which have been worn in an accident and stretched must be replaced by a qualified workshop. Renewal may be necessary even if there is no apparent damage. The belt anchorage should also be checked.

• Do not attempt to repair a damaged seat belt yourself. The seat belts must not be removed or modified in any way.

• The belts must be kept clean, otherwise the retractors may not work properly.