Vibration of Power Hand Tool and Discomfort Experience among Malaysian Industrial Workers

In reality, people who worked with power vibrating tools exposed with the vibrated syndrome that effect their normal life especially who involved for long time period. Hand-arm vibration (HAV) is a widespread hazard in many industries and occupations involving the use of handheld power tools or hand-fed machines. This paper describes a research and observation on the vibrating hand tool. The objective of this study is to measure and compare the grip strength and hand arm vibration before and after using the Ready-Reckoned standard for industrial workers. Continually, an analysis is conducted due to the pain and discomfort experience that face by the workers. This research also do the analysis about the effects of the vibration to the workers hand depend on the duration of handling the power hand tool. Hundred respondent was involved which 50 men and 50 women who had been identified as an industrial worker and working with power hand tools or machinery. The respondents were interviewed and answer Q-Survey that directly conducted at their workplace after doing the test. As the result, worker who works 8 hours per day, the exposure limit value (ELV) is 5m/s, it can cause fatal effects. Most of workers suffered with fingers that gone white on cold exposure and weakness in hand grip.

Stress-Strain-Analysis of Grapevine Pruning with Powered and Non-Powered Hand Tools

Non-power and power cutting hand tools are mainly used every day in vineyards for grapevines pruning during 5 months (November - March). The grapevines pruning with the help of non-power tools is very stressful for wine growers. Repetitive movements combined with external forces in finger-hand-wrist-system, extreme positions in arm-shoulder-system, climate condition are some of the stress factors. Grapevines pruning with 5 manual prunes produced by 3 different manufacture and 2 power hand tools (electrically and pneumatically) were analysed. The results reveal that grapevines pruning with pneumatic and electric prunes is up to 30% more effective (according to productivity) than cutting with non-powered hand tools. At the same time is grapevines cutting with power tools more stressful as with non-powered one.

Dynamics of Power Hand Tools on Operator Hand and Arm Stability

Threaded fastener tightening was studied to determine effects of tool dynamics (torque and build-up time) and workstation configuration (orientation, horizontal distance and height) on operator kinematics and ability to stabilize a right-angle power hand tool. Hand velocity, hand displacement, tool torque, and spindle angle were recorded during tool operation. Four subjects participated. Workstation factors and tool dynamics had significant effects on hand stability. The magnitude of hand velocity and displacement was significantly greater for (1) vertical work surfaces compared to horizontal work surfaces; (2) vertical work surfaces higher than 90 cm above the ground; (3) horizontal work surfaces 90 cm above the ground; (4) increasing torque levels, and (5) long torque build-up times. Subjective ratings of perceived exertion were greater for increasing torque levels, long build-up times, and increasing workstation heights. Perceived exertion was significantly related to hand velocity and displacement ( p<0.05), however, the strength of the correlation was small (R2 ranged between 0.01 and 0.10).