very fact that agricultural machinery uses tremendous power
to do work makes its operation a potential hazard for both the
operator and bystanders. Even though manufacturers try to ensure
that their machinery is as safe as possible, the nature of some
work creates inherent hazards which cannot be removed. Most
accidents with agricultural machinery can be attributed to human
In many cases the operator either forgot something, took a shortcut
or a risk, ignored a warning, wasn't paying close attention
or failed to follow safety rules. Accidents with farm machinery
can be crippling or even fatal. It is important to recognize
and be alert to possible hazards and to take precautions to
There are many different kinds of agricultural machinery - mowers,
tractors, shredders, harvesters, grinders, blowers, augers,
balers, etc. - but they all have similar characteristics and
similar hazards. You can be cut, crushed, pulled in or struck
by an object thrown by these machines.
They can have cutting edges, gears, chains, revolving shafts,
rotating blades, levers and similar hazards. You can also be
injured if you fall while working on or near any of these machines.
Some machine parts cannot be completely shielded in order to
do their job. For instance, a cutting blade cannot be totally
enclosed, or it could not cut. Operators remove guards for maintenance
and often they don't get replaced. This creates a potentially
dangerous situation. Most agricultural machines have similar
or common components to do their work. A basic understanding
of these and the hazards which they pose will heighten your
safety awareness and prevent injury.
points are created when the edges of two objects are moved
closely enough together to cut a soft material, as in the
case of a pair of shears or an auger.
points are created when a single object moves forcefully
or rapidly enough to cut, as in the case of a sickle blade.
and cutting points are created on machinery designed to cut,
as in harvesters, and on those that are not designed to cut,
as in an auger. They are hazards because of their cutting force,
and because they often move so rapidly that they may not be
visible. It can be easy to forget that they are operating.
some cutting and shearing points cannot be guarded, it is
important to be aware of the hazard and to be especially alert
when they are operating.
- It is also important to warn others and to look out for
their safety, because of the danger of thrown objects while
using cutting-type equipment.
points are formed when two rotating objects move together
and at least one of them moves in a circle. For example,
the point at which a belt runs onto a pulley is a pinch
drives, chain drives and gear drives are other sources of
pinch points in power transmission devices. Feed rolls,
gathering chains and similar equipment to draw crops into
the machine also create pinch points.
hands and feet can be caught directly in pinch points, or they
may be drawn into the pinch points by loose clothing that becomes
entangled. Contact may be made by just brushing against unshielded
parts or by falling against them.
can become entangled in pinch points if you take chances
and reach over or work near rotating parts. Machines move
too fast to get out of a pinch point once you become caught
avoid injury from pinch points, be aware of the areas where
pinch points occur and avoid them. Wear clothing that fits
well and is not loose or floppy. Never reach over or work
near rotating parts. Turn off machinery to work on it. Always
replace shields if you must remove them for maintenance.
Rotating shafts are the most common source of wrap point accidents,
although any exposed machine part that rotates can be a wrap
point. A cuff, sleeve, pant leg or just a thread can catch on
a rotating part and result in serious injury. Entanglement with
a wrap point can pull you into the machine, or clothing may
become so tightly wrapped that you are crushed or suffocated.
In other cases, you could be thrown off balance and fall into
other machine parts.
Even a perfectly round shaft can be a hazard if there is enough
pressure to hold clothing against the shaft. Shafts that are
not round increase the hazard significantly. Clothing is more
likely to catch if there is a little mud or dried manure, or
a nick on the shaft. Ends of shafts which protrude beyond bearings
are also dangerous. Universal joints, keys and fastening devices
can also snag clothing.
all equipment for potential wrap points, and shield those
that can be shielded. Place warnings on those that cannot
be covered, or paint them a bright color, perhaps with wide
stripes. Be aware of wrap points and be alert to their danger.
- Crush points are created when two objects move toward
each other or one object moves toward a stationary one.
For example, hitching tractors to implements may create
a potential crush point.
- Failure to block up equipment safely can result in a
fatal crushing injury. A jack may slip, a hose or overhead
support may break, or the equipment may roll. Be sure to
take extra precautions when working with machinery that
is raised for any reason.
- Crushing injuries most commonly occur to fingers that
are crushed at the hitching point. Wait until the tractor
has stopped before stepping into the hitching position.
- If possible arrange the hitch point so that the tractor
can be backed into position without anyone between. Always
know what the other person is doing.
The head or chest of an operator may be crushed between the
equipment and a low beam or other part of a building. Usually,
these accidents occur when operating the machine in reverse
Tree limbs are also potential hazards when working with tractors
and other machinery.
- To prevent being crushed or pinned, first, recognize
the potentially dangerous situations, then, avoid them whenever
- Block all machinery securely if you must work under it.
If an implement can roll freely, block its wheels so it
Many machine parts continue to spin after the power is shut
off. Examples of this are cutter heads of forage harvesters,
hammer mills of feed grinders, rotary mower blades, fans, flywheels,
touch these parts until they have stopped moving completely.
This may take as long as several minutes.
Springs are commonly used to help lift equipment, such as shock
absorbers, and to keep belts tight and may harbour potentially
dangerous stored energy. Springs under compression will expand
with great force when released, and springs that are stretched
will contract rapidly when released.
Know what direction a spring will move and how it might affect
other machine parts when released, and stay out of its path.
Hydraulic systems store considerable energy. They lift implements,
such as plows, change the position of implement components,
such as a combine header or bulldozer blade, operate hydraulic
motors and assist in steering and braking.
Careless servicing, adjustment or replacement of parts can result
in serious injury. High-pressure blasts of hydraulic oil can
injure eyes or other body parts by burning or penetrating the
tissue due to the liquid being hot. Leaks are a serious hazard.
inspect hydraulic hoses with your hands because a fine jet
of hydraulic fluid can pierce the skin. Jet streams from
even pinhole leaks can penetrate flesh. Get medical attention
quickly, or you could lose that part of the body that was
a piece of cardboard to test the hose for leaks. Before
attempting any service on hydraulic systems, shut off the
engine, which powers the hydraulic pump.
the implement to the ground and relieve the pressure. Follow
the instructions in your operator's manual, because the
specific procedures for servicing the systems are very important
to your safety.
points usually occur when someone tries to remove plant
material or other obstacles that have become stuck in feed
rolls or other machinery parts. Always shut off the power
before attempting to clear plugged equipment.
information and recommendations contained in this publication
are believed to be reliable and representative of contemporary
expert opinion on the subject material. The Farm Safety Association
Inc. does not guarantee absolute accuracy or sufficiency of
subject material, nor can it accept responsibility for health
and safety recommendations that may have been omitted due to
particular and exceptional conditions and circumstances.
Copyright © 2002 Farm Safety Association Inc.
22-340 Woodlawn Road West, Guelph, Ontario (519) 823-5600.
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.