Exposure assessment model for hand arm transmitted vibrations considering exposure variability and determinants.
Approximately 350 000 workers are on a daily basis exposed to hand-arm vibrations from a broad diversity of hand held tools. Variability in exposure levels for hand-arm-vibrations are scarcely scientifically investigated.
The vibration exposure is usually measured at a single occasion and not in a systematic way. Research from other fields, for example chemical exposure, display exposure patterns of exposure variability between and within exposed individuals. This variability has a decisive impact on measurement strategies and may impair the exposure-response relationship. Exposure variability and consequences of this variability for hand-arm-vibrations are scarcely scientifically investigated. Therefore, one aim of the study is to systematically measure hand-arm-vibrations and simultaneously observe factors that might influence the exposure. Another important factor is exposure time, which has shown to be difficult to estimate. The second aim is to develop a method to objectively measure the exposure time and to compare the objectively measured data with the workers own time estimates. In field, vibration levels and exposure times are repeatedly measured among the workers using grinding machines and determinant factors will simultaneously be observed. The data collected will be useful for risk assessments, measurement strategies and preventive measures, which in the future will decrease the risk for hand-arm-vibration syndromes.