Seat Ibiza Owner's Manual page 71

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 se-
curely.
Never use seat belt clips, fastening rings or
●
similar items 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 acci-
dent and stretched must be replaced by a
specialised workshop. Renewal may be nec-
essary 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 re-
moved or modified in any way.
● The belts must be kept clean, otherwise the
retractors may not work properly.
Seat belts
Head-on collisions and the laws of
physics
Fig. 84 A driver not wearing a seat belt is
thrown forward violently.
The unbelted passenger in the rear
Fig. 85
seat is thrown forward violently, hitting the
driver who is wearing a seat belt.
It is easy to explain how the laws of physics
work in the case of a head-on collision: when
a vehicle starts moving, a type of energy
called "kinetic energy" is created both in the
passengers and inside the vehicle.
The amount of "kinetic energy" depends on
the speed of the vehicle and the weight of
the vehicle and its passengers. The higher
the speed and the greater the weight, the
more energy there is to be "absorbed" in an
accident.
The most significant factor, however, is the
speed of the vehicle. If the speed doubles
from 25 km/h (15 mph) to 50 km/h
(30 mph), for example, the corresponding ki-
netic energy is multiplied by four.
Because the vehicle occupants in our exam-
ple are not restrained by seat belts, in the
event of crashing against a wall, all of the oc-
cupants' kinetic energy will be absorbed
solely by said impact.
Even at speeds of 30 km/h (19 mph) to
50 km/h (30 mph), the forces acting on bod-
ies in a collision can easily exceed one tonne
(1000 kg). At greater speed these forces are
even higher.
Vehicle occupants not wearing seat belts are
not "attached" to the vehicle. In a head-on
collision, they will move forward at the same
speed their vehicle was travelling just before
the impact. This example applies not only to
head-on collisions, but to all accidents and
collisions.
»
69