Relation between risk values based on internal spinal forces and epidemiological outcomes due to long-term whole-body vibrations
There is some scientific evidence for long-term exposure to whole-body vibration being associated with an increased risk of back disorders and early degenerations of the lumbar spine. According to the EC-directive 2002/44/EC, the daily exposure limit value standardised to an eight-hour reference period should be 1.15 m/s² (A(8)-value) or, by the choice of the member state concerned, a vibration dose value of 21 m/s1.75 (VDV). The corresponding daily exposure action values were defined by 0.5 m/s² and 9.1 m/s1.75. In general, the member states adopted the A(8) values when implementing the EC-directive. There are some doubts whether this value adequately reflects the effects of vibration containing multiple shocks. Moreover, the use of the axis of highest vibration for deriving the A(8) value is under critical discussion. At the present, an ISO working group is dealing with the qualification of ISO 2631-5 in order to improve the risk assessment for vibrations containing shocks. In this context, an FE-model developed at BAuA has been examined. It is supposed that exposure to whole-body vibration causes internal forces within the human body including dynamic forces in the spine. Risk values can be calculated based on the vertical internal spinal forces.
Taking into account the research need mentioned above, the association between the risks for spinal impairments (e.g. self reported low back pain, prolapse) obtained from epidemiological studies and calculated risks based on internal spinal forces in the lumbar spine will be investigated.
Unit 3.1 "Prevention of Work-related Diseases"