Ergonomics
is defined as "the study of how people behave in relationship to their work
and workplace." The basic
principle of ergonomics is that we fit the job to the person, not the person to
the job. This concept may mean
designing your work area so items are within reach and easy to see.
Ergonomics also means lessening the impact of repetitive movements (such
as data keystroking), and the use of good posture.
Today, ergonomics is recognized as a vital element in preventing
injuries, improving conditions, and streamlining productivity.
OSHA
is now making available a working draft of a proposed ergonomics protection
standard that the agency has provided to small business representatives. As
required under the Small Business Regulatory Enforcement Fairness Act, OSHA is
conferring with small businesses about how its working draft ergonomics proposal
might affect them before publishing a proposed rule in the Federal Register.
However, because of the importance of the issue of ergonomics, OSHA is
making the working draft widely available.
It can be accessed on OSHA’s site on the World Wide Web: http://www.osha.gov.
The
draft is a “work-in-progress.” Specific
provisions could change dramatically before a proposed ergonomics program
standard is published in the Federal Register later this year. OSHA must
also prepare a series of economic, risk and other analyses supporting the
proposal. Then the working draft
and accompanying analyses will undergo a series of reviews.
After those reviews, OSHA will publish a proposed rule and provide many
opportunities for public comment.
Work-related
musculoskeletal disorders (WMSDs) are now a leading cause of lost-workday
injuries and workers’ compensation costs.
Many operations in a workplace have
potential for causing injury or illness, each in perhaps a different way.
WMSDs account for 34 percent of all lost-workday injuries and illnesses,
according to Bureau of Labor Statistics. Carpal tunnel syndrome, one form of
WMSD, leads on average to more days away from work than any other workplace
injury. Carpal tunnel syndrome
cases involve more than 25 days away from work, compared to 17 for fractures and
20 for amputations. The amount of physical stress a job produces is often
determined by the:
Posture
you must assume to do your job.
Force
needed to perform the task.
Number
of repetitions of a stressful task.
If
your job activities require repetitive movements for prolonged periods of time,
then an ergonomic approach to performing the job tasks will help avoid
unnecessary injury. Many of the principals outlined in this newsletter can be
used on job sites like your physical plant for carpenters, painters, mechanics,
etc. Use them in your home, too. You may help yourself or a loved one avoid a
painful injury!
Body
is relaxed, with your arms hanging loosely at your sides.
Wrists
are straight.
Shoulders
are relaxed.
Elbows
are close to your body.
Working
surfaces and seats should be designed to eliminate the need to work with a bent
spine.
Ergonomic
problems are especially likely at workstations where you have to:
Bend
your neck forward more than 15 degrees.
Lean
forward or sideways.
Tilt
your head backward, sometimes induced by bifocals.
Crouch
over your work.
Work
with your arms above your head, or out away from body.
Bend
your wrists, especially if work is repetitive or requires forceful movements
Sit
with your head, neck, and back upright. Adjust
the chair back and utilize lower back support. Sit with both feet firmly on the
floor (or a footrest) in front of you.
Awkward
posture, poorly positioned equipment and furniture, and typing or sitting in the
same position for hours can add to wear and tear on your body.
Many
jobs can be performed with less effort when you are standing.
However, prolonged standing can create stresses on the legs and lower
back.
The
height of the work surface should usually be 2-6 inches below the level of your
elbow when the arm is hanging relaxed. Padded
anti-fatigue mats should be supplied for jobs requiring standing for a long time
on hard, unyielding surfaces such as concrete.
Elevating one foot while standing can help reduce low-back stress, and
adjustable footrests are available.
Lighting
must be appropriate to the job. The amount of light needed will depend on the
job, your age and eyesight, and other factors.
Adjust
the lighting to eliminate glare and harsh reflections, keep the monitor screen
at a right angle to outside windows, adjust contrast and brightness, use an
anti-glare screen if necessary, and keep your screen clean.
Since
most modern ceilings are the suspended type, light fixtures are "drop
in" and a fixture located in the center position can usually be moved one
position in any direction (for a total of eight ceiling tiles) to help remove
glare.
Your
monitor and document holder should be slightly below eye level, 14-20 inches
from your eyes, and arranged in a position to reduce glare from windows and
lights.
Adjusting
the divisions of bifocals and trifocals can help when positioning your monitor
and document holders.
Excessive
light can create eye fatigue, so avoid direct or reflected light sources in your
field of vision. The angle from your line of sight to the light source should be
greater than 30 degrees.
Arrange
your material and your screen so that you don't have to swing your head and eyes
back and forth from the material to the screen. This action can make your
muscles become stiff and sore, and cause eyestrain and headaches.
Keep
your forearms, hands, and wrists straight and relaxed.
When you work with straight wrists and fingers, your nerves, muscles, and
tendons stay relaxed and comfortable. With
this posture they are less likely to develop the strains and pains associated
with keystroking and will prevent the possibility of damage to the nerves.
Your
posture at the keyboard affects the position of your neck and head, wrists, and
hands. An adjustable chair will allow you to position yourself at a
proper angle and distance from the screen.
(Other aspects are outlined under "Posture" above.)
Optometrists
recommend an annual eye examination if your job requires prolonged use of a VDT.
Practicing
good ergonomics does not necessarily mean a large cash outlay.
Here are some examples of no-cost or low-cost ergonomic devices.
Chairs:
Many
new inexpensive chairs are ergonomically correct and can be mechanically
adjusted to fit each user. Using
rolled-up towels or pillows can make excellent back supports.
The
seat and backrest of the chair should support a comfortable posture permitting
occasional variations in the sitting position.
Chair height and backrest angle should be easily adjustable.
The
chair height is correct when the entire sole of the foot can rest on the floor
or footrest, and the back of the knee is slightly higher than the seat of the
chair. This allows the blood to circulate freely in the legs and
feet.
Foot
Rests:
A
footrest may be necessary for short individuals. You can use telephone books or
empty boxes as foot rests, or inexpensive models may be purchased.
Keep your feet flat and pointed toward your workstation.
Copystands
or Document Holders:
These
should be at the same height as your monitor screen, to keep you from straining
your neck or head. Inexpensive
models are available, or you may choose to make your own from a cut-up cardboard
box.
Telephone
Headsets:
The
use of a telephone while doing prolonged keystroking can cause neck strain if
ergonomic factors are not considered. Try
a telephone headset to keep your head upright and your body straight.
Monitor
Stands:
Use
one or more large telephone books or empty boxes to raise your monitor to eye
level, or buy a commercial model.
Hold
your head at a slight downward tilt to avoid straining muscles in your neck and
shoulders.
Stands
that swivel horizontally, and tilt or elevate vertically, enable the operator to
select the optimum viewing angle.
Arm
Rests and Wrist Rests:
When
the operator's hands are resting on the keyboard, the upper arm and forearm
should form a right angle. The
hands should be in a reasonably straight line with the forearm.
Long or unusually high reaches should be avoided.
Arm
rests or wrist rests would permit periodic support as needed.
Something as simple as a rolled-up towel can act as a wrist rest.
Glare
Screens:
There
are many inexpensive models available. You may not need to purchase a glare
screen, but only adjust your monitor to face away from a direct light source.
Rest your eyes periodically (every 20-30 minutes) to help lessen the
strain of prolonged keystroking sessions.
PREVENTION
Practicing good ergonomics also means taking frequent exercise breaks to avoid eyestrain, back and neck strain, and hand trauma caused by repetitive motions. Develop a schedule that allows you to perform preventive exercises that can be done at your desk or workstation. Vary your routine.
EXERCISES
AT YOUR DESK
To
keep your eyes from drying out and feeling itchy, try to blink rapidly every
once in a while.
Close
your eyes and cover both eyes with the palms of your hands.
Take a 2-3 minute break with your eyes closed.
Refocus
your eyes; look at an object that is located far from you across the street or
room. Take a two-minute break.
Sit
with shoulders down and relaxed. Gently
let head fall forward as far as you can. Hold
for 5-10 seconds. Gently raise head and repeat up to 5 times.
In
seated or standing position, let arms relax at your sides.
Then raise your shoulders and rotate them up and back in a circular
motion. Repeat up to 5 times, then
change direction.
In
standing position, extend your arms straight out at sides.
Move arms in a circular motion, with the elbows locked.
Repeat 5-10 times in each direction.
With
your hands in front of you and your elbows at a comfortable angle, gently rotate
your wrists. Repeat 5 times in each
direction.
Grasp
the fingers of one hand and bend back the wrist. Hold for 5 seconds, then switch
hands.
Gently
grasp the thumb of one hand and pull out and down until you feel the stretch.
Hold for 5-20 seconds. Repeat
3-5 times with each thumb.
With
your hands in front of you, first make a fist and hold for 5 seconds. Then spread out the fingers as far apart as you can.
Hold for 5 seconds. Repeat
up to 5 times for each hand.
Gently
massage the palm and back of each hand, using a circular motion.
This especially helps the muscle at the base of the thumb.
If you feel you have an ergonomics problem at your workstation, contact your supervisor.