Robert
Wilkinson and Anthony
Tilma
Michigan State University Extension
Much
of the agricultural production work in the United States is
done outdoors; however, many tasks are done indoors. For example,
animals are kept indoors in confinement operations; fruit
sorting and packing work is sheltered or performed indoors;
most plant nurseries are inside operations; and maintenance
and repair tasks are done inside buildings or under shelters
whenever possible.
Consideration
for animal and plant welfare should be a major concern in
farm building design because produce is the revenue source,
but the health and safety of the people who work inside the
same buildings or shelters also have to be considered.
Technology
has done much to improve the environment indoors for people,
animals, and plants, but there are still many problems when
people and animals or people and plants have to share the
same environment.
Safety
should be foremost in any new design plans for buildings and
machinery or equipment, but comfort is also a controlling
factor. Animals and people both perform better when comfortable
and better performance increases the chances for safer farm
work.
The
level of comfort of an individual person or animal is influenced
by environmental conditions such as climatic atmosphere, space,
and light. Over many centuries engineers have endeavored to
make work easier. Modern developments have done much to improve
the working environment for agricultural operations.
There are four important climatic factors:
- air
temperature
- air
velocity
- humidity
- radiation
temperature.
Air
temperature is controlled by air conditioning and heating
and much of today's modern outdoor farm equipment is equipped
with air conditioners. This contributes to safety because
enclosed cabs and filter systems on air conditioning systems
reduce the amount of dust, spores, and potentially toxic particles
breathed by machinery and equipment operators. In the summer,
air conditioning allows longer work periods without endangering
health due to dehydration, sunburn, sun stroke or heat exhaustion,
and fatigue.
The
most efficient operating temperature and conditions for humans
is rarely the same as temperature and conditions for animals.
Because comfort for the animals is important for production,
people have to find ways to make working in animal environments
more acceptable. Some ways to reduce exposure or exposure
time include:
- Using
mechanical help to reduce the time spent in an animal-dominated
environment.
- Rotating
chores among workers whenever possible.
- Using
special clothing and equipment, such as dust filters or
a respirator, when necessary to protect oneself or to provide
more personal comfort.
- Separating
human work areas from areas where the animals are kept.
Separate rooms with conditions set for human comfort allow
workers to be close to the animals without spending all
their work time in the animals' environment.
- Keeping
up-to-date on new developments and enlisting the help of
Cooperative Extension Service and animal environment consultants
to determine what changes can be made and how to make them
in a specific enterprise.
Technology has helped us develop artificial lighting. Most indoor
work requires artificial lighting and artificial illumination
is provided on tractors, combine-harvesters, and other machinery
for work after dark during periods of peak activity.
Four
aspects of lighting should be considered whether artificial
illumination is employed or daylight through windows is used.
Intensity
Light intensity is measurable and is expressed in lux (lumens
per square foot). For efficient work, the required level of
illumination will depend on:
- The
size of objects with which a farmer works.
- Contrast
between the objects and the immediate surroundings.
- Reflectivity
of the object.
- Time
allowed for seeing the object.
- The
age and visual health of the worker.
All
tasks on the farm will not require the same amount of illumination
nor the same type of illumination source.
Contrast
Contrast is used to help distinguish between the objects of
importance (the work piece) and the background. Avoid sharp
contrasts, especially for work in animal areas where shadows
can cause animals to spook.
Glare and flicker
Glare occurs when the field of view contains areas of high brightness
that interfere with vision of the normal task. Limited amounts
of glare may cause only annoyance, but unexpected bright glare
may be a hazard if a worker is temporarily blinded.
Causes
of glare include:
- direct
sunlight,
- bare
lamps,
- reflections
of light or bright sources in glossy or highly reflecting
surfaces, such as glass or mirrors, and
- excessive
differences in illumination of adjacent areas.
Flicker
is annoying, especially when noticed in the peripheral line
of vision. Fluorescent tubes can cause noticeable flicker.
Flicker may also be more noticeable with bluer lamps than
with redder ones. Besides being annoying, flicker can cause
headaches.
Discharge
lamps such as florescent lights can pose a serious danger
when serving as the source of light in areas where rotating
or reciprocating machinery is used. The stroboscopic effect
occurs when the machinery rotates but appears to be slower
moving. The optical effects with moving objects and this type
of lighting can be deceiving.
Color
Color of illumination can be used to advantage for contrasting
the work task or to psychologically enhance the working environment.
Some colors are considered to be "cool" colors while others
are "hot" colors. Temperature effects can be changed by the
use of color without changing equipment or control settings.
Colored
light is also helpful when used to help mark obstacles or
highlight controls, such as red for emergency purposes.
Colored
light can be harmful when it distorts natural colors, lowers
contrast, or decreases working efficiency. In these situations
colored light indirectly increases the risk of injury.
Remember
that human eyes do not see all colors equally well and that
different animals are sensitive to different colors.
Computers are playing an increasingly important role in agricultural
work. Safety is enhanced while the drudgery of various types
of farm work is reduced. The list of uses for computers in agricultural
applications is continually growing.
Computers
and controllers are used to control equipment designed to
maintain climatic comfort inside buildings. Ventilating systems
and fans, furnaces, and air conditioners are turned on and
off according to preprogrammed temperature and humidity settings.
Computers
and/or programmable motor controls can be programmed to control
lights.
Computer-controlled
operations such as feeding and cleaning reduce the chore time
workers spend in animal housing environments, minimize the
amount of fertilizers and pesticides placed in the field,
and help sort and grade fruit.
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
Michigan State University,
Agricultural Engineering Department.
Robert Wilkinson, Anthony Tilma, Agricultural Engineer and former
Graduate research assistant, respectively, Michigan State University
Extension, East Lansing, Michigan 48824. 5/92. Funded by the
National Institute of Occupational Safety and Health - #UO5/CC-4506052-01.
This information is for educational purposes only.
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