Dirk Zeinstra, a mechanical engineer, worked for Shell's global operations for 25 years. In 2000, he started work as a vibration specialist with Beizein, in the Netherlands. Initially Zeinstra focused on machinery vibrations but shifted his attention to the impact of vibrations on people in 2004.
Many kinds of machinery, including forklifts, create vibrations. Vibrations can negatively impact on employees' bodies and sometimes cause permanent disability.
Beizein measures, analyses and calculates the amount of shock and vibration workers receive when working with machinery in factories or small businesses that use production machines like grinders, saws and forklifts.
Employees can suffer painful cramps and lose sensitivity in fingers, hands and arms when exposed to vibration and shocks from machinery. Long-term exposure can lead to knuckle problems and aches in hands, wrists and shoulders. The vibration from tools can narrow blood vessels, resulting in a limited blood flow. Fingers turn white and feel painful. In cold weather, affected body parts ache for short or long periods. The effects are irreversible.
Continuing to use vibrating machinery can cause numbness in employees' fingers. "Dead fingers" result from deformation of small nerves. Once an employee suffers hand-arm vibration syndrome (HAVS), their fingers and hands lose sensitivity. As the symptoms slowly increase in severity, the individual will notice a reduced grip force and less flexibility in their hands.
Other symptoms of exposure to body vibration are tiredness, nausea, blindness, dizziness, back problems, seasickness, reduced accuracy and dislocation of internal organs. Arthritis is a major problem, especially for forklift drivers.
Forklift drivers should be encouraged to drive in a style that minimises exposure to shock and vibration. They should drive slowly and handle loads carefully. Forklifts can be equipped with better tyres and seats to provide comfort for drivers. Other solutions include changing forklift drivers' routes and improving road conditions (potholes, road bumps, etc) caused by normal wear and tear. Employers need to be aware of drivers' conditions as exposure to shock and vibration is serious.
In June 2005, a new European directive was introduced to compel employers to add limb and body vibration in employee risk inventories and evaluation. European directive 89/391/EEC, article 16, paragraph 1, compels machinery and tool manufacturers to bring vibration to the lowest possible levels. Manufacturers must incorporate vibration levels into user guidelines for each tool. Vibration is measured in m/sec2 for eight hour (A8) daily doses. When the 0.5m/sec2 (A8) threshold is passed, the body must be protected. When 2.5m/sec2 (A8) is passed, hands and arms must be protected. When those values are exceeded, manufacturers and employers must show workplace safety regulators they have plans in place to reduce employee exposure to vibration.