Tool Safety: Some tips on reducing tool-related injuries

Feb. 1, 2002

Tool Safety
by Joe Escobar

The working environment of an aircraft mechanic is filled with hazards. From toxic chemicals to high sound levels, we must always be diligent at working safely. But one area that can sometimes be neglected is in the area of tool safety. This article will briefly discuss some things that can be done to help prevent injuries that are caused by our everyday tools.

General safety rules
In terms of general safety rules, The Occupational Safety and Health Administration (OSHA) recommends the following five basic safety rules to help prevent hazards associated with the use of hand and power tools:
• Keep all tools in good condition with regular maintenance.
• Use the right tool for the job.
• Examine each tool for damage before use and do not use damaged tools.
• Operate tools according to the manufacturers' instructions.
• Provide and use properly the right personal protective equipment.

Another good safety tip to note is to maintain a clean work area. Accidental slips can cause severe injury when working with any types of tools.

In addition to these general guidelines, there are some specific safety rules associated with each class of tool used.

Hand tools
Hand tools can include anything from hammers to safety wire pliers. According to OSHA, the greatest hazards posed by hand tools result from misuse and improper maintenance. If a chisel is used as a screwdriver, the tip of the chisel may break and fly off, injuring the user or other employees. If a wooden handle of a tool such as a rubber mallet is loose, splintered, or cracked, the head may fly off and cause injury. If the jaws of a wrench are sprung, the wrench might slip. If impact tools like rivet sets have mushroomed heads, the heads might shatter on impact, sending sharp fragments flying toward the user or other employees.

Remember that whenever using cutting tools like saw blades or knives, they should be directed away from the aisle areas and away from other employees working in close proximity. Also keep knives and scissors sharp; dull tools are more dangerous than dull ones.

Keep in mind that iron or steel hand tools may produce sparks that can be an ignition source around flammable substances. When working in a fire hazard area, spark-resistant tools made of non-ferrous materials should be used. This includes areas where flammable gases and highly volatile liquids are stored or used.

Power tools
Power tools include electric and pneumatic tools. The following general precautions should be observed whenever working with power tools:
• Never carry a tool by the cord or hose.
• Keep cords and hoses away from heat, oil, and sharp edges.
• Disconnect tools when not using them, before servicing and cleaning them, and when changing accessories such as blades, bits, and cutters.
• When possible, secure work with clamps or a vise, freeing both hands to operate the tool.
• To avoid accidental starting, do not hold fingers on the switch button while carrying a plugged-in tool.
• Follow instructions on the user's manual for lubricating and changing accessories.
• Be sure to keep good footing and maintain good balance when operating power tools.
• Wear proper apparel for the task. Loose clothing, ties, or jewelry can become caught in moving parts.

Safety guards must never be removed when a tool is being used. Although sometimes a bit of an inconvenience, removing a guard can introduce many dangers to the job task.

Electric tools
The most serious hazards associated with electric tools are electrical burns and shock. Shock can lead to injuries or even heart failure. Under certain conditions, even a small amount of electric current can result in heart fibrillation and death. An electric shock can also cause the user to fall off of a ladder or other elevated work surface and be injured due to the fall.

In order to protect yourself from shock and burns, electric tools must have a three-wire cord with a ground and be plugged into a grounded receptacle, be double insulated, or be powered by a low-voltage isolation transformer. Note that whenever using an adapter to accommodate a three-wire plug into a two-hole receptacle, the adapter wire must be attached to a known ground. The third prong must never be removed from the plug.

Double-insulated tools provide potection against electrical shock without third-wire grounding. On double-insulated tools, an internal layer of protective insulation completely isolates the external housing of the tool.

The following general safety guidelines are applicable to working with electric tools:
• Operate electric tools within their design limitations.
• Store electric tools in a dry place when not in use.
• Do not use electric tools in damp or wet locations unless they are approved for that purpose.
• Ensure that cords from electric tools do not present a tripping hazard.

Pneumatic tools
There are several safety issues concerning pneumatic tools. Foremost of them is the danger of getting hit by one of the tool's attachments (such as a rivet set).

Pneumatic tools must be checked to see that the tools are fastened securely to the air hose to prevent them from becoming disconnected.

If an air hose is more than 1/2 inch in diameter, a safety excess flow valve must be installed at the source of the air supply to reduce pressure in case of hose failure.

The same general precautions should be taken with an air hose that are recommended for electric cords because the hose is subject to the same kind of damage and can also cause tripping hazards.

When using a rivet gun or air hammer, always install a safety clip or retainer in order to prevent the set from being ejected during operation. Never point rivet guns toward anyone or "dead-end" them against yourself or anyone else.

Noise is another issue associated with pneumatic tools. Wear appropriate hearing protection as required.

These have been some general safety guidelines when working with tools. Ultimately, it boils down to awareness. By being aware of the hazards posed by the tools and being alert to our surrounding work environment, we can help avoid tool related injuries in the workplace. AMT

The information in this article is from OSHA's booklet "Hand and Power Tools" OSHA 3080. To download this or other OSHA documents, you can go to You can also find links to other Safety and Compliance websites on