Using noise exposure histories to quantify duration of vibration exposure in tree fallers

A study of tree fallers in the British Columbia forest industry was done to determine if noise histories could be used to monitor the daily duration of exposure to hand-arm vibration from chain saws. Field observations and noise dosimetry showed that chain saw noise was distinguishable from other sound sources in fallers' work environments. Using data from noise dosimetry synchronized with observations of fallers' chain saw use, a model of sound pressure levels predictive of chain saw operating mode was developed. Subsequent workday noise histories of 13 fallers showed that the chain saw was off for an average of 331 +/- 27 min, idling for 91 +/- 11 min, and cutting wood for 96 +/- 7 min. This method could be used to collect data to refine dose-response estimates for vibration syndrome or to monitor administrative controls of vibration exposure time.