Nail Gun Safety

A nail gun does in a second what a hammer does in five swings, and it can put a nail through a hand, a knee or an eye just as fast. By 2011, when OSHA and NIOSH published a joint guide, nail gun injuries were sending about 37,000 people a year to emergency rooms, most with hand and finger wounds. Framers, roofers, siding and deck crews, trim carpenters and pallet builders all use these tools, and the same habits protect all of them.

OSHA rules for pneumatic tools are in 29 CFR 1926.302. Nailers with automatic feed that run above 100 psi must have a safety device on the muzzle, so they fire only when the nose is against the work. That safety does not make the tool safe by itself. Your trigger choice and your habits do that.

What You Will Be Able to Do

• Tell a sequential trigger from a contact trigger and pick the right one.
• Set up and check a nailer before you use it.
• Keep your hands and your body out of the nail's path.
• Clear a jam without firing a nail into yourself.
• Say what to do after a nail gun injury.

How the Triggers Work

Every nailer has a safety contact at the nose and a trigger under your finger. The order they have to be pressed in decides how dangerous the tool is.

Other styles sit between these two, such as a single sequential trigger, and some tools have a selector switch. Check the tool, not your memory. The manual and the label on the tool tell you which trigger is installed.

The OSHA and NIOSH guide found that the risk of a nail gun injury is about twice as high with a contact trigger as with a full sequential trigger. It recommends full sequential triggers as the first and best step for any crew. Studies cited in that guide found that the speed gained with contact triggers is small on most work.

A contact trigger is sometimes allowed for open framing and sheathing, where speed matters most and the nail lands in a predictable place. Some employers ban it. Use a sequential trigger for everything else, including toenailing, nailing overhead or in tight spots, trim and finish work, and most roofing. If you are new, use sequential only.

Warning: With a contact trigger, holding the trigger while you walk or climb is the same as carrying a loaded tool with the safety off. If the nose bumps your leg or a stud, it fires.

Why People Get Hurt

Most injuries come from a short list of causes. Knowing them tells you what to avoid.

• Double fire. The tool recoils and, with a contact trigger, bounces back onto the work and fires a second nail before you can react.
• Bumping the nose by accident. The trigger is held down and the nose touches something, such as your leg while you climb a ladder.
• Ricochet. A nail hits a knot, a metal strap or another nail and comes out somewhere else.
• Going through the wood. A nail passes through thin stock or misses the edge and hits the hand holding it.
• Awkward positions. Reaching, nailing overhead or nailing toward your own body puts you in the path.
• Bypassed safeties. A taped trigger or a wired-back nose removes the protection, and it is never allowed.

Before You Start

1. Read the label. Know the trigger type, the operating pressure and the fasteners the tool takes.
2. Inspect the tool. Check that the safety contact moves freely and springs back. Check the trigger, magazine, hose and fittings. Tag out a tool with a stuck or damaged safety.
3. Connect the air. Use the pressure on the tool's label. Framing nailers commonly run around 100 psi for long nails like a 3-1/2 inch framing nail, and many tools allow about 70 to 120 psi. Use the lowest pressure that sets the nail flush. Too much air drives nails too deep and increases recoil.
4. Test on scrap. Point the tool at scrap and fire a couple of nails to check the depth.
5. Put on your PPE. You need safety glasses or goggles marked ANSI Z87.1 at a minimum, hearing protection, and a hard hat where one is required. People nearby need eye protection too.

Cordless nailers skip the hose but not the rules. Treat a battery as you would an air line: take it out before you clear a jam or adjust the tool.

Safe Nailing Habits

• Keep your finger off the trigger except when you are ready to place a nail. Do not hold it while you carry the tool.
• Carry the tool at your side by the handle, pointed down. Never carry it by the hose, and never point it at anyone, even as a joke.
• Keep your free hand at least 12 inches from the nail point. Use a clamp or a block to hold short pieces.
• Place the nose flat against the work before you fire. Angled shots are more likely to skip or ricochet.
• Watch for knots, metal connectors and other nails. Move your shot away from them. Use the correct tool or hand nail metal connectors.
• Nail away from your body and away from other people. Know who is on the other side of the wall or below the deck.
• Stay balanced. Do not reach beyond the ladder rails or over an edge. Move your feet instead.
• Stay clear of edges of thin stock where the nail may blow out the side.
• Keep the hose out of the way. A hose across a walkway or over an edge is a trip hazard and it can pull you off balance.

Disconnect Before You Touch It

Disconnect the air, or remove the battery, whenever you:

• Clear a jam.
• Load nails, if the manual calls for it.
• Adjust or repair the tool.
• Leave the tool, go up or down a ladder, or pass it to someone else.

Clearing a jam:

1. Take your finger off the trigger.
2. Disconnect the air hose or remove the battery. Press the nose against scrap wood and pull the trigger once to confirm that it does not fire.
3. Remove the nails from the magazine if the manual calls for it.
4. Open the nose latch and clear the bent nail with pliers, not your fingers.
5. Close the latch, reload, reconnect and test on scrap.

If the Tool Acts Up

If Someone Gets Hurt

Treat every nail wound as serious, even a small one. A nail can carry dirt and pieces of glove into the wound, and it can hit bones, tendons or nerves. It can also have barbs and glue that make it hard to pull out.

1. Stop work and disconnect the tool.
2. Leave an embedded nail in place. Do not pull it out.
3. Control bleeding with pressure around the wound, not on the nail.
4. Get medical care right away. For a nail in the head, chest, abdomen or eye, call 911.
5. Tell the doctor about the nail type, and ask about a tetanus booster.
6. Report the injury, and report near misses too. A nail that went through a glove without breaking skin is a warning about how that task is being done.

Check Your Understanding

1. You are toenailing studs in a tight corner with a nailer set to contact trigger. What should you change?

Switch to a sequential trigger. Toenailing in a tight spot is an awkward position with a high risk of ricochet and double fire.

2. Your nailer jams on a ladder. What is the first thing you do?

Take your finger off the trigger, get down safely, and disconnect the air. Do not clear the jam on the ladder with the air connected.

3. You need to nail a 6-inch block and your fingers would be right beside the nose. What is safer?

Hold the block with a clamp, or cut it from a longer board and trim it after nailing. Keep your hand at least 12 inches from the point.

4. Your coworker taped back a sticky safety contact so the tool will keep firing. What do you do?

Stop using it, take the tape off, tag the tool out and tell your supervisor. Bypassing a safety is never allowed.

5. A nail went through a coworker's boot and into the foot, but it does not hurt much. What is the right move?

Leave it in place, get medical care and report the injury. A small wound can still damage tissue or get infected.

Key Takeaways

• A full sequential trigger is the safest choice and the default for new users.
• A contact trigger roughly doubles the risk of injury.
• Keep your finger off the trigger and your free hand 12 inches from the point.
• Disconnect the air or battery before clearing jams, adjusting, or leaving the tool.
• Wear eye and hearing protection every time.
• Get every nail wound looked at, and report near misses.