Heavy Vehicle Seat Vibration

Past research has associated whole-body vibration exposure with a number of adverse effects on the human body. The effects of vibration on the lower back and spine have been extensively researched and documented. Effects on the gastrointestinal system have received less attention but are considered by some to be significant.

The following points summarise the findings of the literature review:

* There is some laboratory and field research that supports a relationship between low frequency vibration (3 Hz) and increased fatigue or drowsiness. This may have implications for heavy vehicle truck drivers who usually experience vibration levels around this frequency while driving.
* Intermittent and random vibration can have a stimulating or wakening effect.
* Vibration exposure has been found to cause changes to body metabolism and chemistry that could lead to fatigue effects.
* The health effects of whole-body vibration have been extensively researched and adverse effects have been established. Truck drivers shown many of the symptoms of adverse health effects associated with whole-body vibration exposure.
* Typical whole-body vibration exposure levels of heavy vehicle drivers are in the range 0.4 - 2.0 m/s2 with a mean value of 0.7 m/s2 in the vertical (z-axis). Vertical vibration is highest in the frequency range 2 – 4 Hz.
* The average whole-body vibration level experienced by drivers of heavy transport vehicles exceed health, fatigue and comfort limits of the Australian Standard and most exposures are within the Caution zone (for health) according to the current International Standard. Many typical exposures will reach the likely health risk zone of the International Standard. According to these standards, many truck drivers are at risk of incurring adverse health effects from prolonged exposure to vibration.
* There is evidence that truck drivers have back complaints that could be partly attributable to whole-body vibration exposure.
* Comfort limits of both Australian and International Standards are exceeded by most vehicle rides.