Since their introduction in 1959, pneumatic nail guns or nailers have increased productivity in woodworking, manufacturing and construction immeasurably. Nail guns have replaced hammers in many tasks, and made fastening much easier, but at the same time that efficiency boost has come at a cost.
According to the Centers for Disease Control (CDC), there are an estimated 37,000 to 42,000 emergency room visits each year involving nail gun injuries. Most injuries involve puncture wounds to the operator’s hand and fingers, but there are many bystanders or workers injured by deflected nails and fasteners. Studies show as high as 12% of injuries are received by persons, other than the operator. Studies have also found that as many as two out of five apprentice carpenters will experience a nail gun injury in their first four years of work. Approximately 75% of injuries are soft-tissue related, and 25% structural; Bone and joint fractures or impalement.
There are many factors that result in a nail gun injury:
• Lack of training
• Using nailers only in Contact Trip Mode
• Improper hand placement
• Deflected nails and fasteners
• Workers keeping their finger depressed on the trigger while moving, carrying the tool, and walking
• Overriding or rendering safety devices and guards inoperable
• Personal protective equipment not being used
Mode Selection Sequential Trip
A sequential trip (also called restricted) is the safest mode available. It gets its name from the “sequence” required to operate it. To drive a nail, the worker must first place the nailer’s or fastener’s nose or tip against the nailing surface and then pull the trigger. To drive a second nail, the worker has to lift the tool from the work surface, release the trigger, and then repeat the two-step sequence above. Using Sequential Trip may result in lower productivity, but it’s the safest mode for operation.
Contact Trip
With a contact trip (also called bump or bounce) pneumatic nailer, the worker depresses the trigger and places the nailer’s tip against the nailing surface. Every time the safety contact tip is depressed as it hits the material surface, a nail fires. Obviously, this mode increases the margin of error or accident. This mode is commonly used in pallet nailing applications, but it does require extra operator care to ensure safety.
As in all tool operation and job tasks, safety training is crucial in accident prevention. The following is a
list of safety rules, that when followed, will prevent most injuries related to pneumatic nailers and fasteners from occurring:
Always provide operational safety training on the tools that the worker will be using, prior to their initial assignment, and at least annually thereafter.
Never allow workers to operate any tool or equipment that they have not received training on.
Report all hazards, close calls, and accidents to your supervisor immediately.
When employees are unsure, or unfamiliar of the tools they will be operating, they must request training from their supervisor.
Always follow the owner’s manual to understand safe operation and maintenance of the tools you will be using.
Sequential Trip mode is the safest mode for operating nailers and fasteners. When using the nailer or fastener in Contact Trip mode, operators must remain safety conscious of the speed of nailing, and placement. They must always ensure that they remove their finger from the trigger guard area when not intending to nail or fasten.
Always wear safety glasses. All safety glasses must be NIOSH approved.
Always wear hearing protection.
Never point the nail gun toward yourself or anyone else, even if it doesn’t contain nails or is disconnected from the air supply.
Always make sure the area behind the nailing surface is clear of people.
Never hold down the trigger unless the nose of the nail gun is pressed against the item to be nailed.
Always disconnect the nail gun air supply when leaving it unattended, clearing jammed nails, or performing any other maintenance.
Maintain and lubricate nailer and fasteners according to the manufacturer’s recommendations.
Never use a nail gun that’s defective, for example, with loose bolts, screws, or fittings. Any tool that is unsafe should be tagged “DO NOT OPERATE” and taken out of service until properly repaired.
Inspect replacement nails for proper fit and damage before inserting them into the gun.
Complete a daily pre-use safety check of the nailer and energy supply.
Follow the directions in the user manual to clear jammed nails.
Ensure that all repairs or maintenance are completed by competent and authorized person.
Always hold the tool away from the body while carrying it.
Keep guards and other safety devices on nailers and fasteners working in accordance with the manufacturers’ recommendations.
Never render the safety devices or guards of any nailer or fastener inoperative.
Always assume that the nailer or fastener is loaded and contains fasteners.
Never carry the tool with your finger on or under the trigger; always remove your finger from the trigger area when not driving nails or fasteners.
Drive nails/fasteners into the work surface only, never into materials that are too hard to penetrate.
Do not drive nails/fasteners close to the edge of the work surface, on top of other nails/fasteners or with the tool at too steep an angle, which could cause the nails/fasteners to ricochet and hurt someone.
Remove all nails/fasteners from the tool before connecting it to the air compressor and do not exceed the manufacturer’s recommended working air pressure rating.
Securely fasten the air hose to the tool to prevent it from becoming disconnected.
Never use the air hose to hoist the tool
Always used compressed air to operate the tool. Never use compressed gas or bottled gas to operate the tool.
Nails and fasteners should not be corroded or rusty; this will cause the gun to jam or otherwise malfunction.
Keep pneumatic nailers and fasteners away from other people and children.
To assure the nailer or fastener will operate correctly and safely, always follow the manufacturer’s recommendations for maintenance.
Never place your hand directly behind the surface that will be nailed or stapled. Your free hand should be a minimum of 1 foot or 30 centimeters away.
Editor’s Note: Jary Winstead is a safety consultant, author and trainer who serves a variety of industries, including the forest products sector. He owns Work Safety Services LLC and can be reached at SAFEJARY@gmail.com.
