Vibration energy transmitted from a simulated tool handle to human fingers and the palm of the hand.
Dong-RG; Wu-JZ; McDowell-TW; Welcome-DE; Schopper-AW
Proceedings of the 38th UK Conference on Human Response to Vibration, September 17-19, 2002, Gosport, England, 2002 Sep; :455-460
A methodology is developed to measure the distribution of the vibration energy/power transmission at human fingers and the palm of the hand. The study involved six adult male subjects, a constant-velocity (14 mm/s) sinusoid vibration in the frequency range of 16-1,000 Hz, and three different hand-handle coupling conditions (grip-only, combined grip and push, and finger pull-only/palm push-only). The results indicate that under a regular hand-tool coupling condition, the power transmitted into the fingers is considerably less than that into the palm at low frequencies (<40 Hz). The transmission into the fingers is, however, either higher or comparable to that into the palm at frequencies higher than 160 Hz. The effect of the coupling condition on the power transmission generally reduces with the increase of frequency. At frequencies higher than 63 Hz, the power transmitted to the fingers under the same contact force but different palm coupling actions can be generally considered the same for practical applications. The characteristics of the power transmission distribution suggest that the risk of vibration-induced finger disorders at high frequencies may be underestimated when using the constant-velocity weighting as specified in the current ISO 5349, and the power transmitted to the palm may have a better association with vibration-induced disorders in the palm-wrist-arm structures.
Vibration-exposure; Vibration-effects; Vibration; Tools; Hand-injuries; Hand-tools; Vibration-disease; Arm-injuries; Humans; Ergonomics
Disease and Injury: Musculoskeletal Disorders of the Upper Extremities
Proceedings of the 38th UK Conference on Human Response to Vibration