Mechanical testing and evaluation of D3O® material for adequacy of an ergonomic intervention for vibration transmission reduction in aircraft manufacturing

Abstract

Daily exposure to vibrations produced by hand-held percussive vibratory power tools can be detrimental to aircraft manufacturing sheet metal mechanics. ISO (5349-1, 2001b) indicates that symptoms of the hand-arm vibration syndrome, which may develop within 10 years of exposure, depends on the magnitude, frequency, and duration of vibration exposure and on his/her susceptibility. The American National Standard Institution (ANSI, S2.7-2006) identifies the maximum daily exposure limit value among individuals exposed to hand-arm vibration for an 8-hour workday at or above 5.0 m/s2 results in a high health risk. This research evaluates an ergonomic intervention using a new material called D3O® to reduce the vibration transmission to the hand-arm and elbow during a riveting and bucking task. This research evaluates two studies, a static test for energy absorbency and a dynamic test for impact force resistance, which were conducted to test the mechanical properties of three D3O® foam materials and two traditional silicone elastomers. The static test revealed D3O® materials had a higher energy absorbency than silicone elastomers (p = 0.00). Material DBP, DRH, and DRP show a dampening ratio of 0.16, 0.11, and 0.10 compared to SFP and SSP of 0.05. Comparing between D3O® materials, results show a statistically significant difference in the way materials resist and dampen impact forces during dynamic testing. Material DBP ranks 1st and DRP ranks 3rd consistently. Material DRH ranks 3rd during the static test and ranks 1st during the dynamic test. Using D3O® materials may result in a higher dampening of the magnitude of vibration produced during riveting and bucking tasks. These results suggest utilizing D3O® in an ergonomic intervention to evaluate vibration transmission to the hand-arm and elbow to reduce WMSDs. A limitation of the material testing is that it does not take into account human hand tissue and the vibration produced in a riveting task.