Solution Summary: Extracting Pliers
Extracting pliers feature auto-locking jaws and a curved heel that reduces the gripping force required when extracting nails or staples.
An extracting plier is an engineering control that reduces awkward hand and wrist postures and hand fatigue. The auto locking jaws only require the worker to keep both jaws in contact with the object being removed. If slippage occurs, the jaws of the pliers increase the gripping force, reducing the amount of gripping force. The curved heel allows the worker to push down to pull the object out without awkward hand and wrist postures.
Extracting pliers weigh 21 ounces, are 11 inches long, and are made from chromium molybdenum steel with a black phosphate covering to resist rust and corrosion. The jaw features 22 teeth and is 15/32 inches wide. The jaws are parallel, allowing maximum contact with the object being extracted (Figure 1). This tool can be used to remove nails, screws, staples, rusty or damaged fasteners, pneumatic fasteners, brads, and cleats.
Figure 1. The extracting pliers
To operate, the object to be removed is gripped with the jaws. The handles are gripped until resistance is met which locks the jaws on the object. The worker then pushes down towards the side of the curved heel which removes the object (Figure 2).
Figure 2. The extracting pliers in use.
Stressful hand and wrist activity can cause musculoskeletal disorders (MSDs) such as muscle strains; tendonitis, which is inflammation of elbow and wrist tendons; or carpal tunnel syndrome, which is compression of a wrist nerve, resulting in finger numbness and loss of hand strength. The extracting pliers can help reduce stressful hand and wrist activity by requiring less gripping force and a more neutral hand and wrist posture when extracting objects.
How Risks are Reduced:
Extraction of objects with traditional pliers requires repetitive or forceful gripping of the handles to prevent the object from slipping out of the jaws. The claw of a hammer may not be able to remove all types of objects. Extracting pliers do not require repetitive or forceful gripping and can remove various objects. The curved heel allows the worker to utilize leverage and push down to pull the object out. In addition, removing an object with traditional pliers often requires awkward hand and wrist postures. An extracting plier is operated with a more neutral wrist position.
The manufacturer states that the extracting pliers “…will never slip off. This unique ability takes place without squeezing the handles, only requiring the user to keep both jaws touching the object.” The manufacturer also states that the extracting pliers’, “Auto-locking jaws mean the user will not experience hand cramps from squeezing the handles…. [The] curved heel enables the fastener to be lifted, with minimal damage to surface.”
Safety and health experts believe that the extracting pliers reduce demand on the worker because it eliminates repetitive and forceful gripping and awkward hand and wrist postures.
Effects on Productivity:
The extracting pliers increase productivity on the worksite.
An extension pipe can be used on the upper handle to provide increased leverage during extraction (not included).
Dan Anton, PT, PhD, ATC; and Kevin Wright, SPT – Eastern Washington University