Chainsaw Safety

A chainsaw cuts wood fast, and it cuts legs just as fast. It is used to clear storm damage, trim grounds, cut timber on a job site, and take down trees. The risk stays the same in each case. Most serious injuries come from a handful of habits: no leg protection, poor footing, bad cuts, and kickback. The focus here is safe use on the ground. Felling a standing tree, cutting under load, and using a saw aloft need hands-on training from a qualified person.

What You Will Be Able to Do

• Choose the right protective gear
• Do a pre-use check on a saw
• Start a saw safely
• Explain what causes kickback and how to prevent it
• Read tension and compression in a log
• Sharpen and fuel a saw safely

Protective Gear

Wear all of it, even for a quick cut.

Chaps are filled with long fibers that pull out and jam the drive when the chain touches them. They must cover the front of your legs from the waist to the top of your boot. In the US, ASTM F1897 is the common performance spec, so look for chaps marked to it. Replace chaps that have been cut. Washing and wear also reduce their protection, so follow the maker's care rules.

Pre-Use Check

Check these with the engine off.

1. Chain tension: The chain should sit snug on the bar, and you should be able to pull it around by hand with gloves on. Loose chains come off. Tight chains overheat.
2. Chain sharpness: A sharp chain pulls itself in and throws chips. Fine dust means it is dull.
3. Bar: Look for bends, worn rails, or plugged oil holes.
4. Chain brake: Engage it, and make sure the chain will not move.
5. Throttle lockout: The throttle should not move until you press the lockout.
6. Chain catcher, handles, and muffler: All should be in place and tight.
7. Bar oil and fuel: Fill both. Running without bar oil ruins the bar and chain.
8. Air filter: Clean it if it is dirty.

Do not use a saw with a broken brake or a missing part.

Fueling

Let the saw cool before you refuel. Fuel on bare ground, away from sparks and at least 10 feet from where you will start it. Wipe up spills. Use the fuel mix the maker specifies. Do not smoke.

Starting

Start the saw on the ground, or firmly held against something solid, with the chain brake on.

1. Place the saw on firm, level ground, away from people and fuel.
2. Engage the chain brake.
3. Set the choke if the engine is cold.
4. Hold the front handle with your left hand. Put your right foot through the rear handle, or follow the method in the manual.
5. Pull the starter with smooth, firm pulls.
6. Once it starts, set the choke to run, and release the brake only when you are ready to cut.

Never drop-start a saw by swinging it in the air as you pull the cord. It leaves you with a running saw and only one hand on it. Safety rules prohibit it.

Kickback

Kickback is the most dangerous thing a saw does. It happens when the upper part of the bar tip touches something, or when wood pinches the chain. The bar rockets up and back toward your head and neck, faster than you can react.

To prevent it:

• Know where the bar tip is at all times. Do not let it touch logs, branches, or the ground.
• Cut with the lower part of the bar when you can.
• Hold the saw with both hands, with your thumb wrapped under the front handle.
• Keep the chain sharp.
• Use a low-kickback chain unless you are trained for something else.
• Keep the brake working. It stops the chain, but it does not stop the saw from moving toward you.

Where Not to Cut

Do not cut:

• Above shoulder height. You lose control, and the saw is near your face.
• With one hand. You cannot control a kick.
• Between your legs. Anything that goes wrong goes straight to your legs.
• While standing on a ladder. A slip and a running saw are a deadly mix.
• Near other people. Keep at least two tree lengths from anyone when felling, and well clear when cutting on the ground.

Stand to the side of the saw's path, with your feet apart and on firm ground. Clear brush so that you can step back. Keep your body out of the line of the bar.

Carrying a Saw

When you walk with a saw, set the chain brake, or shut the engine off. A common rule is to do this whenever you take more than two steps. Carry it with the bar pointing behind you and the muffler away from your body. Use a scabbard for travel.

Reading Wood Under Tension

Wood that has fallen or bent stores energy. It can pinch your bar or spring out at you.

• Compression side: The wood is being squeezed. It closes on the saw as you cut.
• Tension side: The wood is being stretched. It opens as you cut, and it can spring out suddenly.

Worked example. A log rests on the ground at each end and sags in the middle. The top is in compression and the bottom is in tension. Cut about one-third of the way down from the top, then finish from below so that the cut opens and does not pinch.

Storm damage is full of this stored energy. A bent sapling or a tree under a load can whip with deadly force. Spring poles, tree roots lifting a root plate, and tangled trees all need a trained worker. If you are not sure how a piece will move, leave it.

Felling Is a Separate Skill

Felling standing trees takes training. The cuts, escape routes, and judgment are not something to work out alone. Do not fell a tree that is leaning, dead, or near power lines, buildings, or roads unless you are trained and authorized. Stay away from any tree that is near or touching a power line, and call the utility.

Keeping the Chain Sharp

A sharp chain is a safer chain. You should not need to force a saw.

1. Set the chain brake and secure the bar in a vise, or on a stump vise.
2. Use the round file size for your chain, as the maker lists it.
3. File at the angle marked on the file guide, usually about 25 to 35 degrees.
4. Give each cutter the same number of strokes.
5. Use a depth gauge tool to check the rakers and file them if they are high.
6. Replace the chain when the cutters are worn down.

Many operators touch up the chain at each refill. Wear gloves while filing.

If Someone Is Cut

Saw injuries can bleed fast. Shut down the saw, call 911, and press hard on the wound. Use a tourniquet if you are trained and bleeding from a limb will not stop. Never work alone with a saw. Keep a first aid kit that can handle heavy bleeding, and make sure the crew knows the site address.

Common Mistakes

Check Your Understanding

1. You are making fine dust and pushing hard on the saw. What is wrong?

The chain is dull. Stop and sharpen it. Forcing a dull chain tires you and raises the risk of kickback.

2. A coworker starts a saw by dropping it while pulling the cord. What do you say?

Stop them. Start the saw on the ground with the brake on. Drop-starting leaves a running saw in one hand.

3. A log is supported at both ends and sags in the middle. Which side will pinch your bar?

The top, because it is in compression. Cut part way down from the top, then finish from below.

4. You need to walk 30 feet to the next log. What do you do with the saw?

Set the chain brake or shut it off. Carry it with the bar pointing behind you.

Key Takeaways

• Wear chaps, head and face protection, hearing protection, and boots each time.
• Check the brake, chain, and bar before you start.
• Start on the ground with the brake on. Never drop-start.
• Keep the bar tip away from everything to avoid kickback.
• Never cut above your shoulder, with one hand, or between your legs.
• Leave felling, spring poles, and power line work to trained people.