Power tools can reduce the risk of musculoskeletal disorders (WMSD) when manual hand tools require frequent and repetitive use of force. Always conduct a risk assessment before making any changes to ensure that one type of hazard has not been exchanged for another. Make sure that all aspects of the new tool have been considered (weight, size, etc.). [1]

When selecting and using hand tools, remember to:

• Bend the tool, not the wrist; use tools with angled or bent handles when appropriate.
• Avoid high contact forces and static loading.
• Reduce excessive gripping force or pressure.
• Avoid extreme and awkward joint positions.
• 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 vibration.
• Minimize the amount of force needed to activate trigger devices on power tools.

[2] Basic tips for using hand tools:

• Make sure that employees are properly trained in the safe use of hand tools.
• Always provide training on how to choose the right tool for the job, how to correctly use each tool, and how to identify when tools need repair.
• Select the right tool for the job. Substitutes increase the chance of having an accident.
• Use tools designed to allow the wrist to stay straight. Avoid using hand tools with your wrist bent.
• Use good quality tools.
• Keep tools in good condition at all times.
• Inspect tools for defects before use. Replace or repair defective tools.
• Keep cutting tools sharp and cover sharp edges with a suitable covering to protect the tool and to prevent injuries from unintended contact.
• Replace cracked, splintered, or broken handles on files, hammers, screwdrivers, or sledges.
• Make sure that the handles of tools like hammers and axes fit tightly into the head of the tool.
• Replace worn jaws on wrenches, pipe tools and pliers.
• Redress burred or mushroomed heads of striking tools.
• Pull on a wrench or pliers. Never push unless you hold the tool with your palm open.
• Point sharp tools (e.g., saws, chisels, knives) laying on benches away from aisles, and handles should not extend over the edge of the bench top.

[6] When using woodworking machines, adhere to these safety tips:

• Keep the area free from water and moisture. Do not use electrical equipment outdoors in the rain.
• Always keep your attention on the work. For example, if you must talk to another person, turn off the equipment first.

[3] When using woodworking machines, avoid:

• Wearing loose clothing, work gloves, neckties, rings, bracelets or other jewellery that can become entangled with moving parts.
• Awkward operations and hand positions where a sudden slip could cause your hand to move into the cutting tool or blade.
• Standing directly behind stock that is being cut, planed, or jointed to avoid injury from kick-back.
• Removing sawdust or cuttings from the cutting head by hand while a machine is running. Use a stick or brush when the machine has stopped moving.
• Using compressed air to remove sawdust, turnings, etc. from machines or clothing.
• Leaving machines running unattended (unless they are designed and intended to be operated while unattended). Do not leave a machine until the power off is turned off and the machine comes to a complete stop.
• Trying to free a stalled blade before turning the power off.
• Distracting or startling an operator while he or she is using woodworking equipment.
• Horseplay, as it can lead to injuries.
• Performing maintenance on the machine unless all hazardous energy is controlled.

[3] Some basic tips when using hand tools include:

• Maintain tools carefully. Keep them clean and dry, and store them properly after each use.
• Carry tools in a sturdy toolbox to and from the worksite.
• Wear safety glasses or goggles, or a face shield (with safety glasses or goggles) and well-fitting gloves appropriate for the hazards to which you may be exposed when doing various tasks.
• Keep the work environment clean and tidy to avoid clutter, which may cause incidents.
• Use a heavy belt or apron and hang tools pointed down at your sides, not behind your back.
• Keep the work space tidy. Store tools properly when not in use.

[5] When using hand tools, avoid:

• Using tools for jobs they are not intended to do. For example, do not use a slot screwdriver as a chisel, pry bar, wedge or punch, or wrenches as hammers.
• Applying excessive force or pressure on tools.
• Cutting towards yourself when using cutting tools.
• Holding the stock in the palm of your hand when using a cutting tool or a screwdriver. Always lay it on a workbench or in a vice.
• Wearing bulky gloves to operate hand tools.
• Throwing tools. Hand them, handle first, directly to other workers.
• Carrying tools in a way that interferes with using both hands on a ladder, while climbing on a structure, or when doing any hazardous work. If working on a ladder or scaffold, tools should be raised and lowered using a bucket and hand line.
• Carrying a sharp tool in your pocket.

[5] Several work factors can affect the health and performance of hand tool users, including:

• Static load on arms and upper body muscles
• Awkward working positions and body postures
• Tissue compression

[7] To ensure a good grip, sufficient friction must exist between the hand and the handle. Hand tools should be made of non-slip, non-conductive, and compressible materials. Textured rubber handles provide a good grip, reduce effort, and prevent slipping. Avoid glossy coatings and highly polished handles. Handles made of plastics or compound rubber are recommended for electrical and heat insulation. Sharp edges and contours can be covered with cushioned tape to minimize lacerations. [1]

Tool design, workstation design, and task scheduling are key factors in safe hand tool use. An effective prevention strategy must address all aspects simultaneously. [4]

When selecting a tool, consider the following weights:

• 2.3 kg (5 lb) if the hand tool will be used away from the body or above shoulder height.
• 1.4 kg (3 lb) or less for tools operated with one hand
• 0.4kg (1 lb) for precision tools to allow for good control.

[4] Tools above these weight recommendations should be supported with a counterbalance, tool holder, articulating arm, or straps as appropriate. [4]

Ensure the center of gravity is aligned with the gripping hand. Tools should feel "easy" to hold in either an upright position or in the position it will be used. Avoid drills that are "front-heavy" as they require extra effort to hold in a usable position. An exception is a power hand tool, such as a grinder, that has to be heavy in order to reduce the force that the worker has to exert while using it. [8]

Tool handles and grips should be designed for a power grip, allowing the operator to align their fingers towards the palm, using their entire hand for a stronger grip, except for precision work tools. [8]

Tools with "bent" or angled handles or tools with pistol grips are beneficial where the force is exerted in a straight line in the same direction as the straightened forearm and wrist, especially when the force must be applied horizontally. [8]

Select tools that do NOT require wrist flexion, extension or deviation. In other words, select tools that allow you to keep the wrist straight or in a neutral position. [10]

Cylindrical or oval handles at 40mm (1.5 in) offer a better power grip, ranging from 30-50mm (1.25 to 2 in). For precision grips, a diameter of 12mm (0.45 in) is recommended, with a range of 8-16mm (0.3 to 0.6 in). [10]

Tool handles should be not less than 100 mm (4 in) to reduce the negative effects of any compression exerted. Handles around 120 mm (5 in) are generally recommended. Keep in mind that the use of gloves requires longer tool handles. [10]

The recommended distance separating the handles on crushing, gripping or cutting tools is between 65-90 mm (2.5 to 3.5 in). Grips that are larger than 100 mm (4 in) will be difficult for some users. Tools with larger or smaller spans will reduce one's maximum grip strength. [10]

Even the best tool on the market will not transform a poorly designed workstation into a safe and comfortable one for the operator. Many work space components, such as work surfaces, seats, flooring, tools, equipment, environmental conditions, etc., determine whether or not the job is safe and healthy. If the workplace design does not meet your physical needs, it can create risk factors for discomfort, aches and pains, fatigue, and, eventually, WMSDs. On the other hand, in a well-designed workplace, where you can choose from a variety of well-balanced working positions and to change between them frequently, work can be carried out safely and injury-free. [11]

To help prevent work-related musculoskeletal disorders (WMSDs), avoid bending over your work; instead, keep your back straight and, if possible, elevate the work area or task to a comfortable level. Keep your elbows close to the body, and reduce the need to stretch your arms overhead or out in front of you. Tool extensions can help where it is difficult to reach the object of work. Using a stepladder or step stool can improve the working body position, where the task requires elevating your arms above the shoulder. At the same time, frequent stretching breaks will relieve any built-up muscle tension. If standing, distribute your weight evenly between the feet. Use a footstool or rail to rest your legs, and shift from one to the other periodically. [9]

For precision work, provide the worker with a height-adjustable workstation. For a fixed-height workbench, provide work platforms to accommodate shorter workers, and raise the work surface for taller workers. Provide sufficient leg clearance to allow the worker to get close to the work object, thereby reducing the need to bend the torso. Provide a footrest as foot support to improve body balance and minimize the static load on the worker's back. [9]

For assembly work, use tool balancers to reduce the effort of holding and operating the tool. If possible, use the lightest tool to get the job done properly, preferably one weighing less than 1 kg (2 lbs). Anti-fatigue matting reduces lower back and leg discomfort and minimizes fatigue. [14]

Jobs that involve using only one kind of tool for one or a few tasks that do not vary in the movements and muscles used can cause an overload of those muscles, ligaments, tendons or tissues. The resulting overload on the same part of the body can cause pain and injury. A greater variety of tasks allow for changing body position to distribute the workload over different parts of the body, and to give overtaxed muscles some relief and recovery time. Rotate tasks among workers; have workers move from one task to another according to a schedule. Ensure tasks are different in the type of movement and body parts used. [12]

Training workers on the safe use of tools and the hazards involved in working with them has always been extremely important. The introduction of a new tool or equipment and any change in the way the job has been done previously should be preceded by refresher training that includes new information relevant to the changes being introduced. Even the best- designed tool, the most ergonomically correct workstation, or the most up-to-date work organization will fail to prevent injuries if the worker is not properly trained. [13]