The ergonomic concerns related to hand tool design

When should power tools be used?

When handheld manual tools are used for tasks that require frequent and repetitive force when performing tasks the risk of contracting an musculoskeletal disorder significantly increases. An practical replacement for a much lower risk method is high on the hierarchy of controls when it comes to solutions for ergonomic risk. Which is why introducing the use of power tools that can effectively make the job more efficient and reduce forceful motions. First, conduct a risk assessment before assessing the need for changes. When considering a tool, make sure that all aspects of the new tool have been considered (weight, size, etc.) to be sure that a tradeoff for one type of hazard has not been exchanged for another.

What ergonomic risk factors are unique to powered hand tools?

Power tool triggers

Frequent use of the index finger to actuate the trigger of power tools (i.e. power drill) poses a considerable risk for trigger finger (tendonitis in the finger) and trigger thumb (tendonitis in the thumb). A longer trigger allows the use of two or three fingers to activate them, which minimizes the risk for injury as more muscles and tendons are recruited.

Vibration

Vibration is a significant ergonomic risk factor and exacerbates other risks. The most effective way to reduce vibration in power tools is at the design stage. This fact makes tool selection most critical. Anti-vibration materials will dampen only some of the vibration above certain frequencies that are characteristic for the kind of material used.

What should one remember when selecting and using hand tools?

When selecting and using hand tools it is important to:

·       Choose tools that do not require bending of the wrist and rather tools with angled or "bent" handles, when appropriate.

·       Avoid high contact forces and static loading.

·       Reduce excessive gripping force or pressure.

·       Avoid twisting hand and wrist motion by using power tools rather than hand tools.

·       Avoid repetitive finger movements, or at least reduce their number.

·       Avoid or limit the vibration transferred to the hand.

·       Minimize the amount of force needed to activate trigger devices on power tools.

How does hand tool maintenance reduce the risk for injury?

The condition of tools is also an important factor. For instance, blunt or dull tools such as scissors, saws, cutters, in a poor state of repair, not only compromise safety but also increase the effort needed to use them significantly. Tools in poor condition should be discarded or restored to optimum condition.