Introduction
You Are the Most Important Factor of Your Own
Safety.
What Saw Should You Choose?
Anti-Kickback Devices
What Should You Do To Prepare For Cutting?
What Clothing Should You Wear?
What's The Big Deal About Kickback?
What Jobs Are Not For You and Your Chain Saw?
What Jobs Should You Leave For The Professional?
Chain Saw Troubleshooting
Fire Prevention
Other Safety Rules to Remember
Limbing
| Do
you know approximately what percentage of all woods accidents
in a year are typically the result of a chain saw cut?
Do you
know how fast a chain saw blade can move at full throttle?
Do you
know which age group of operators are at the greatest risk
for injury?
Do you
know how many of all chain saw accidents could be prevented?
|
Chain
saws are powerful tools that make your job of cutting firewood
and fallen trees and removing small trees much easier. But
their power makes them very dangerous tools.
Most
accidents are the result of a moving chain contacting the
operator in some way.
The
good news for you is that there are several things you can
do to keep yourself from becoming a victim.
Return
to Table of Contents
How?
1. Know
your saw and how to operate it before you use it. That means
reading and understanding your operator's manual. If there
are instructions you do not understand, talk to your chain
saw dealer or to someone who is very familiar with how to
use your chain saw.
2.
Take the time to prepare for the job. This includes several
factors discussed in this information fact sheet and probably
in your owner's manual.
3.
Practice! Begin with logs on which you can make trial cuts
to get the feel of your saw and the way it handles.
4.
NEVER WORK ALONE! At least be within yelling distance of
help.
Even if
you have used your saw a few times before, or you've used it
once a year for the past several years, these are still important
steps to take and precautions to think about.
Return
to Table of Contents
The
best saw for you is the one you can comfortably handle and is
appropriate for the type of work you do most often.
| Lightweight
saws |
good
for occasional use: cutting limbs, firewood and small trees |
| Midweight
saws |
better
for more frequent use |
| Heavyweight
saws |
for
PROFESSIONAL use only |
There
are also many safety features you should look for -- NOTE
that these features do not prevent accidents, they only reduce
the risk to you.
Return
to Table of Contents
Chain
brake stops the chain if kickback occurs. This can mean
the difference between possibly a speed of 45 MPH and 0 MPH
if the chain actually contacts you.
Throttle
Interlock prevents the throttle from accidentally advancing
or inadvertently moving by automatically returning the throttle
and chain to idle when the trigger button is released.
Hand
Guard will keep the left hand from slipping into the chain.
Balance
is not a device, but something to look for. You can maintain
better control over the saw that is well balanced in your
hand if kickback occurs.
Anti-kickback
chains reduce the forces on the chain that cause kickback.
Return
to Table of Contents
Clear
Your Work
Area:Make sure there are no nails in the wood or loose objects in the area where you are cutting, such as twigs, brush, leaves and stones.
Check
Your Chain's Condition and Sharpness:
(Follow
the instructions in your manual and use the proper maintenance
tools.)
Sharpness-
a sharp chain make the chainsaw easier to use.
Tension-
if the chain is too loose, it may derail and cause a severe
injury; but if it is too tight, it may bind and also cause
an accident or damage to the chainsaw.
Idlespeed-
prevents the chain from rotating when the controls are in
the idle position.
All
nuts and screws should be tight. Everything should be well
lubricated.
Fuel
the Saw in a Safe Place:
Completely
wipe off any spilled fuel and move the chainsaw to a new location
before starting the engine.
Check
the Conditions in Which You Are Cutting:
If you are
felling a tree, make sure you consider which way the wind is
blowing in deciding which direction the tree should fall. Also
look for a lean in the tree and a heavy imbalance if several
large limbs are all on one side of the tree. IN EVERY CUTTING
SITUATION you must make sure you have secure footing. If the
ground is slippery from rain, snow or ice, then you should not
cut there. Always look for broken limbs or other trees caught
in the tree you want to cut.
Plan
Your Escape Route:
Make sure
there are no obstacles that can cause you to trip. Then, after
you have made your cut, you will be able to move rapidly at
least 25 feet away from the tree at a 45-degree angle without
any hazard. If you have an electric saw, be careful not to trip
over the cord.
Assess
Your Own Physical Condition:
Cutting
with a chain saw is physically demanding, even for strong persons,
so do not use a chain saw if you are not physically able to
handle it. And take plenty of rest breaks before you get tired.
BE ALERT! Otherwise you put yourself at a severe risk.
Under
NO circumstances should you be under the influence of ANY
substance -- this includes drugs, alcohol AND cold medicines
-- that can impair your vision, dexterity or judgement.
Return
to Table of Contents
Wearing
the proper clothing is one of the best safeguards for you to
reduce the possibility of serious injury.
- Wear
sturdy, snug-fitting clothing that gives you complete freedom
of movement. Do not wear anything loose that could catch
in the moving chain, such as sleeve cuffs, cuffed pants,
scarves, loose long hair (tie it back), jewelry or (if you
are female) a skirt.
- Heavy
duty, non-slip gloves will improve your grip and protect
your hands from abrasions, cuts and splinters.
- Sturdy
boots with non-slip soles ensure good footing; and protective
toes and high top boots protect your feet and ankles.
- Wear
a non-fogging, vented face screen or safety goggles to prevent
injury from flying chips or a chain that may break off and
fly toward your face.
- Wear
an approved safety hard hat. If it is properly fitted, it
will be cool, comfortable and provide protection from falling
limbs.
- Chain
saws are very noisy, so ear muffs or ear plugs are essential
to protect your hearing.
- Chaps
made for use when using chainsaws protect your legs from
severe cuts should the chainsaw slip.
Return
to Table of Contents
Kickback
is one of the greatest saw hazards. It occurs when a force throws
the saw rapidly and sometimes uncontrollably towards you. It
is a very violent and sudden motion which can severely or fatally
injure you. There are several causes:
- an
abrupt change in wood character -- hitting a knot or a nail
- striking
a nearby limb with the tip of the moving chain while cutting
- running
the chain too slowly
- twisting
the saw in your cut so the chain grabs
- using
a dull or loose chain
- having
a loose grip on the saw or cutting with only one hand
- not
paying attention
But
kickback can be prevented by a few steps and precautions on
your part. These DO NOT PREVENT kickback completely, but they
do reduce the possibility of it happening to you.
-
Always hold the saw firmly with both hands and keep
the left arm as straight and stable as possible
-
Use a saw equipped with a chain brake, anti-kickback
chain, or other Anti-kickback devices.
-
BUT, do not rely exclusively upon safety devices.
-
Watch for twigs that can snag the chain -- the area
should be free from any obstructions.
-
Cut with the lower part of the saw blade-not with the
tip or nose.
-
Maintain a high saw speed when entering, cutting and
leaving the wood cut.
-
Keep the chain sharp.
-
DO NOT cut above mid chest height -- the saw is too
close to your face.
-
DO NOT cut brush or shrubbery.
-
Use only replacement bars specified by the manufacturer.
|
The
more you understand kickback and what it can do to you and
your saw, the better chance you have of controlling its surprise
movement by keeping your balance and control over the chain
saw.
Return
to Table of Contents
If
possible, have a buddy with you so that you do not have to work
alone; but NEVER allow someone else to hold the wood while you
cut.
You
should also reposition the log between cuts, NOT while the
chain saw is still running or in your hand.
Never
cut small, flexible branches or brush with your chain saw.
Their size and flexibility can easily cause the saw to bounce
toward you or bind up with enough force to cause a kickback.
The best tools for that kind of work are a hand saw, pruning
shears, an axe and other hand tools.
Return
to Table of Contents
Some
jobs are too risky for you to try. They may be jobs that require
a heavyweight saw, special training or years of experience.
- Do
not fell medium to large trees because it is very complicated
and dangerous. Leave it to the pros.
- Do
not work from a ladder or from within the tree. Leave it
to the pros.
- Do
not do boring cuts because it is very risky unless you are
trained for the job. Leave it to the pros.
Return
to Table of Contents
If
you are having difficulty cutting or the saw is cutting poorly,
there are several problems you should consider:
- the
chain is dull
- the
chain is improperly sharpened
- the
chain is installed backwards
- the
chain is not properly tensioned
- the
bar and chain are not properly lubricated
- the
guidebar is damaged
- the
exhaust ports are dirty
- the
fuel filter is dirty
- the
air filter is clogged
- the
spark plug is fouled
Your
chain saw will also give you clues when it is time to sharpen
the chain.
- when
you notice the chain tends to walk sideways while cutting
- when
the cut produces fine powder instead of chips
- when
you find yourself pressing down hard to keep cutting
- when
you smell burnt wood
- when
it takes considerably longer to complete cuts made in less
time earlier on the job
Return
to Table of Contents
Gasoline
and the hot chain saw engine can be contributing factors in
starting fires in the woods. You should take precautions to
prevent fires.
There
are five very important rules to remember:
1. NEVER
fuel a saw while the engine is running.
2.
NEVER fuel a hot saw.
3.
NEVER smoke or have any type of flame while you are around
a saw or during fueling.
4.
NEVER start the saw where you fueled the engine.
5.
Keep leaves and dry materials away from the hot muffler.
Return
to Table of Contents
- BEFORE
starting the engine, make sure the chain is not contacting
anything.
- DO
NOT let the saw rest on your leg or knee while you start
the engine.
- Do
not drop start the chainsaw
- ALWAYS
maintain control by standing securely holding the saw firmly
and taking your hand off the trigger between cuts.
- DO
NOT work when you are fatigued.
- Keep
the handles dry and clean and free from the oil and fuel
mixture.
- Whenever
you are cutting, be sure your body is clear of the natural
path the saw will follow when the cut goes through.
- NEVER
straddle the log to make a cut.
- ALWAYS
shut off the engine before setting the chain saw down: even
when you are retreating from a falling tree
- Make
sure the saw is off and the chain has stopped before making
any adjustments or repairs.
- Do
not run the saw indoors.
Return
to Table of Contents
- Stand
on the opposite side of the tree whenever possible, using
it as a barrier between yourself and the limb you are cutting.
Do not overstretch yourself to do this because you are less
stable.
- Do
not face the limb you are cutting squarely -- stand at a
45-degree angle to prevent the saw from striking your leg
if it slips.
- If
you are on a hill, stand on the upside of the hill.
- NEVER
cut limbs above mid-chest height.
- Do
not cut limbs that are supporting the log.
Dr.
Glen H. Hetzel and J. Butler, Agricultural Engineering Department,
Virginia Tech
This
publication was developed with funds from the Center for Disease
Control/National Institute for Occupational Safety and Health,
Project UCS/CCU 306075-03-1.
October
1996
Disclaimer and Reproduction Information: Information in
NASD does not represent NIOSH policy. Information included in
NASD appears by permission of the author and/or copyright holder.
More
