Effects of anti-vibration handle use on hand grinding machine vibration

Hand–arm vibration (HAV) is a kind of local vibration which affects upper extremities. Statistics information revealed the prevalence of vascular and neural disorders among large angle grinder users. The major aim of the study was to evaluate anti-vibration handle’s effect on Hand–arm vibration syndrome. 12 large grinder’s operators from one of the metal processing industries of Isfahan participated in the study. Medical variations consisted of numbness, tingling, bleaching, weakness, itching, coldness, pain, cyanosis and redness. Measuring of vibration performed in 3 axes and according to vibration to international standard ISO 5349–2001. In order to damp vibration, an anti-vibration handle was designed and made, based on spring damper’s low. All data collected from the survey was analyzed by SPSS10 software. Result of McNemar test indicated a significant reduction in vascular and sensory neural symptoms. In addition, by using anti-vibration handle, the transmitted vibration acceleration to hand, were reduced in x, y and z axis by 49, 41 and 47 percent respectively. Using anti-vibration handle, the root mean square acceleration of vibration attenuated to under action level 2.8 m/s2. Findings of the study revealed that making use of the anti-vibration handle could help to prevent incidence of vascular and sensory–neural symptoms. Also, whenever the vibration acceleration attenuates to less than 2 m/s2 we could expect reduction in incidence of Hand–arm vibration syndrome.