Vibrations

The term 'vibrations' generally refers to the more or less regular variation in one or more physical magnitudes (e.g. speed, acceleration) around an average value. Thus, operators of earth-moving machinery and tractors, lorry drivers, crane operators and operators of fixed machines, such as presses, sledgehammers and punches, are exposed to 'whole-body vibrations'.

Mechanical vibrations are transferred in various ways to the human body. For whole-body vibrations, vibrations are transmitted either through the feet of someone who is standing, or through the buttocks of a seated person. These vibrations have an effect on muscular function, breathing and the circulatory system, the autonomous nervous system, sensory perception, and biomechanical modifications. During prolonged exposure, there is a risk of injury of the spinal column and even the internal organs.

Vibrating machines that are held or operated by hand, such as drills, angle grinders, chainsaws, etc., generate 'hand-arm' vibrations.

Hand-arm vibrations are caused by vibrating hand tools. High coupling forces of the hands on the wrist lead to increased transmission of vibratory energy and trigger greater effects.

After only a short exposure time, circulatory problems appear in the hands, and these become chronic after a few years. In addition, disorders of the nervous system, and bone, joint and muscle alterations, can occur.