Hand-arm Frequency-weighted Vibration Effects on Tactility

This study reports results of an investigation into the short-term effects of power hand tool vibration on deep sense tactile sensitivity. Five subjects operated a simulated hand tool using a 30 s / 30 s work~rest duty cycle. The handle vibrated at 1S0 5349 weighted acceleration of 8 m / s 2, for frequencies of 20 Hz, 80 Hz, and 160 Hz, in three orthognal directions. A no-vibration condition was also included for a control Tactile sensitivity of the distal index finger was measured after 30 minutes using a ridge detection threshold detection task. The average falling ridge threshold increased five times from 0.01 mm for the no-vibration condition to 0.05 mm at 160 Hz, however no rising ridge threshold shifts were observed. Implications for job design and work practices are discussed. RELEVANCE TO INDUSTRY Power hand tool vibration effects on tactility should be considered when performing tactile inspection tasks such as sanding operations and inspecting for rough edges or smoothness. Loss of tactile sensitivity may result in reduced quality and work performance.