Although using powered hand tools may help reduce employee exposure to ergonomic risk factors such as repetition and force, they can expose employees to vibration. Vibration restricts the blood supply to the hands and fingers, which, depending on the vibration level and duration of exposure, can contribute to an ergonomic injury. Signs and symptoms of vibration-induced injury, such as Reynaud's phenomenon, start with occasional numbness or loss of color in the fingertips. They progress to more frequent and persistent symptoms affecting a larger area of the fingers and resulting in reduction in feeling and manual dexterity.
Factors that increase the amount of employee exposure to vibration include:
- Bad power tool design - Even new tools can expose employees to excessive vibration if they are not designed with devices that dampen or shield employees from vibration.
- Poor power tool maintenance.
- Old power tools.
General controls to reduce vibration:
- Use low vibration tools.
- Use vibration dampeners or shields to isolate source of vibration from employee.
- Inspect and maintain power tools regularly.
- Limit the duration of tasks that involve vibration, and rotate tasks.