Introduction to vibration
Vibration, usually found in machines, are oscillations - repetitive or periodic movements - around an equilibrium point, where opposing forces or influences are balanced. These can be like a pendulum or random, such as a tire on a gravel road. Vibration motions of engines, electric motors or mechanical devices are often unwanted and undesired.
A handheld drill, for example, creates regular mechanical vibrations as the oscillations are constant. The oscillations may change in speed or intensity depending on how the drill is used but are always there.
Vibration exposure occurs when contact with a vibrating machine transfers vibration energy to parts of the body, such as hands. Anyone exposed to vibration is potentially at risk from developing loss of feeling and sensations in their fingers, hands and arms.
The higher the level of vibration and longer someone is exposed to it, the greater there is of risk of suffering harm from the exposures.
Workers worldwide are exposed to excessive occupational vibrations that puts their health at risk. It can also affect those around them. The effects of exposure depend upon characteristics of the vibration, including frequency, duration and amplitude. When these characteristics are poorly controlled, this can lead to issues such as hand-arm vibration (HAV) or whole-body vibration (WBV), which can both impair the worker's ability to do work tasks.