F. R. Willsey
Purdue Extension
Farm
machinery uses power to do work. This creates a number of
possible hazards for both operators and bystanders. Even though
manufacturers take many steps to make machinery safe, all
hazards cannot be removed.
Most
accidents with machinery are the result of human error. 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.
In many
cases, accidents with farm machinery are very serious, even
fatal. It is important to recognize and be alert for machine
hazards and to take precautions to avoid injury.
There
are many different kinds of farm 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 have cutting edges,
gears, chains, revolving shafts, rotating blades, levers and
similar hazards. You can also be injured if you fall while
working from or near any of these machines.
Another
problem with machinery is that some machine parts cannot be
completely shielded and still do their job. For instance,
a cutting blade cannot be totally enclosed, or it could not
cut. In addition, guards which can be removed for maintenance
often don't get replaced.
Shear
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. Cutting points are created
when a single object moves forcefully or rapidly enough to
cut, as in the case of a sickle blade.
Both
shear 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, so it is easy to forget that it is
operating.
Because
some cutting and shearing points cannot be guarded, it is
important to be aware of their 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.
Another
hazard of farm machinery is the pinch point. Pinch 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 point. Belt
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.
Fingers, 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. You can
become entangled in pinch points if you take chances and reach
or work near rotating parts. Machines move too fast to get
out of a pinch point once you become caught in it.
To 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.
Check
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 farm 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 possible.
Block all machinery securely if you must work under it. If
an implement can roll freely, block its wheels so it cannot
roll.
Many
machine parts continue to spin after the power is shut off;
for instance, cutter heads of forage harvesters, hammer mills
of feed grinders, rotary mower blades, fans, flywheels, etc.
Never touch these parts until they have stopped moving completely.
This may take as long as 2 - 2 1/2 minutes.
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 another machine part when released, and stay
out of its path.
Hydraulic
systems contain fluid under very high pressure. Before loosening,
tightening, removing or otherwise working with any fittings
or parts, relieve this pressure. Jet streams from even pin-hole
leaks can penetrate flesh. In addition, the liquid is often
hot. Before attempting any service on hydraulic systems, shut
off the engine which powers the hydraulic pump. Lower 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.
A federal
child labor law affects you. Unless you are working for your
parent or guardian on a farm owned or operated by that person,
you are not permitted to operate a tractor over 20 pto hp
and certain other farm machines, although some of these jobs
can be started at age 14 if you have special training. Check
with your county Extension office for further details.
Young
people under 14 may be employed to do any job that is not
classified as particularly hazardous if they have the written
consent of their parent or guardian. There is one exception:
children under 12 are not permitted to work on farms that
used 500 or more man-days of labor during any quarter of the
preceding calendar year.
New
1/77
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
NASD Review: 04/2002
S-73
Purdue University Cooperative Extension Service
West Lafayette, IN 47907
Prepared
by F. R. Willsey, former Purdue staff member in Agricultural
Engineering
Approved
for reprinting by Bill Field, Extension Safety Specialist
For
more information, contact Bill Field, Agricultural and Biological
Engineering, phone: 317-494-1191 or e-mail: field@ecn.purdue.edu
Cooperative
Extension work in Agriculture and Home Economics, state of
Indiana, Purdue University, and U.S. Department of Agriculture
cooperating; HA. Wadsworth, Director, West Lafayette. IN.
Issued in furtherance of the acts of May 8 and June 30, 1914.
Purdue University Cooperative Extension Service is an equal
opportunity/equal access institution
|