1. Essential Ergonomics for
Computer Engineers
Name : Venkatesan .M.C
Reg no : 10109205045
B. Tech IT, III yr,
Aalim Muhammed Salegh
College of Engineering.

2. Introduction:
Ergonomics is the scientific study of human work conditions, especially the
interaction between man and machine. Ergonomics is a term taken from the
Greek work "ergon," meaning work, and "nomos," meaning natural laws. The
goal of ergonomics is to make work more comfortable and to improve both
health and productivity. It is an interdisciplinary science of designing the job,
products, and place to fit the worker. Psychology, industrial engineering,
computer science, biomechanics, and safety engineering all play a role in
ergonomics.
The objectives of Ergonomics are shared by Engineering Psychology, which are
to optimize the effectiveness and efficiency with which human activities are
conducted as well as to improve the general quality of life through "increased
safety, reduced fatigue and stress, increased comfort and satisfaction.".
Biometrics and Anthropometrics play a key role in this use of the word
Ergonomics. Engineering Psychology often has a specialty dealing with
Workplace or Occupational Ergonomics.
Most people often think that computer professionals are less prone to
health disease since they are bound to their chairs, but its wrong. In reality,
computer professionals are exposed to elevated health hazards. Computer
professionals need to sit in front of their computers for long time to gain a
better knowledge about them and to use it productively. The computer
engineers especially need to master their machine, on the other hand their
counterpart the machine itself is vulnerable to failure and requires delicate
implementation and maintenance routines.
If you don't pay attention to ergonomics, the activities you do may, over
time, lead to a musculoskeletal disorder. This group of physical problems
usually affects soft tissues (muscles, tendons, and nerves) and joints. Although
MSDs most frequently affect the back and wrists, your whole body is actually
at risk. MSDs can damage fingers, elbows, and shoulders, as well as the neck
and arms, and even the legs. Left untreated, an MSD may limit your range of
motion or reduce your ability to grip objects.

3. Repetitive Strain Injury :
Repetitive Strain Injury (RSI) is the general word that is used to describe the
prolonged pain experienced in shoulders or hands or neck or arms. Repetitive
Strain Injury is the common word used for referring the types of soft tissue
injuries like the nerve spasms, trigger finger and carpal tunnel syndrome.
Muscle Tension + Incorrect Posture + Repetitive Motion + Over-Use = RSI
The term Repetitive Strain Injury is generally used to describe the overused
syndrome associated with particular repetitive activity. They are generally
caused by the work-associated activities such as using computer keyboards and
mouse. The term includes a group of disorders that most commonly develop in
workers using excessive and repetitive motions of the head and neck extremity.
RSI occurs when the movable parts of the limbs are injured. Repetitive
Strain Injury usually caused due to repetitive tasks, incorrect posture, stress and
bad ergonomics. Repetitive Strain Injury generally causes numbness, tingling,
weakness, stiffing, and swelling and even nerve damage. The chief complaint is
the constant pain in the upper limbs, neck, shoulder and back.
The main cause of this main are the repetitive activities, forceful activities
of arms and hand and awkward postures. The other causes of Repetitive Strain
Injuries are sitting in a fixed posture and poor working ergonomics.
The Repetitive Stress Injury generally effects the group of workers who
generally use excessive and repetitive motion of the neck and head are at high
risk. The work pattern of computer professionals carries a lot of orthopedic
disorders. For the people who work on computer for more than few hours a day,
who use musical instruments and who work in production line are at risk of
Repetitive Strain Injury.
The Repetitive Stress Injury is not a life threatening injury for it can cause
pain and disability. The Repetitive Strain Injury is the most worse as it may lead
to permanent incapacity. As Repetitive Strain Injury recovery is being a slow
process, it is better to take treatment at early stage itself.
Repetitive Strain Injury -Symptoms:
1. The users experience constant pain in the hands, elbows, shoulders, neck,
and the back. Other symptoms of Repetitive Stain Injury are cramps,
tingling, and numbness in the hands. The hand movements of the user

4. may become clumsy and the person may find it difficult even to fasten
buttons.
2. Another variant of Repetitive Strain Injury is that, it may produce painful
symptoms in the upper limbs, but the site may be difficult to locate.
3. The common diagnoses seen in RSI are Carpal Tunnel Syndrome,
Tenosynovitis, Bursitis, White Limb, and Shoulder pain. A major cause is
due to long unbroken periods of work. Ergonomics or the lack of it plays
a very important role. Lack of information about the condition leads to
neglect by the concerned individuals.
Carpal Tunnel Syndrome
Carpal tunnel syndrome (CTS) is a compression of the median nerve
in the wrist. Symptoms include pain and numbness in the hand (especially
at night), clumsiness, paresthesia (pins and needles), and trophic changes
(such as muscle wasting). In a true CTS, these are felt where the median
nerve goes: the palm side of the index and middle fingers and part of the
thumb and ring finger. Conservative treatment without surgical
intervention will usually give relief, especially if done early after onset.
Similar symptoms can also be due to nerve compression in the neck,
shoulder or arm from such things as tight neck or shoulder muscles (ie:
thoracic outlet syndrome or pectoral muscle contracture) or poor neck
mechanics to name a few. These other problems are often mis-diagnosed as
CTS. To help see if you have a true carpal tunnel syndrome or not, use
Phalen's test.

5. Phalen's Test
Place the backs of both of your hands together and hold the wrists in
forced flexion for a full minute. (Stop at once if sharp pain occurs) . If this
produces numbness or "pins and needles" along the thumb side half of the
hand, you most likely have Median nerve entrapment (Carpal Tunnel
Syndrome). Examination by a health care professional familiar with these
conditions is the way to be sure of the diagnosis and get proper treatment.
Treatment
Effective conservative treatment of CTS should include:
• Chiropractic manipulation of the wrist, forearm and hand
• Ice massage (10 to 12 minutes) several times a day
• minimizing any irritating activities
• wrist strengthening exercises
• wrist stretching exercises
• possible use of wrist brace or splint while sleeping
• applying sound ergonomic principles

6. Eyestrain:
Eyestrain is a symptom that manifests when we exploit our eyes over an
extended period of time, through activities such as reading or viewing an
electronically-lit screen.
It includes the following
• Pain, dryness or redness around the eyes
• Fatigue
• Sensitivity to light
• Headache
• Difficulty in performing visual tasks
• Blurred vision, Double vision
Work in spurts:
The computer is built for nonstop work — but we aren’t a machine. We
have to take regular breaks to recharge, and so do our eyes. The twenty-twenty
rule is easy to remember: every twenty minutes take a twenty sec break. That is
pull out the eyes away from the computer and stare off into space or an object
that’s approximately 20 feet away from you. In an office, take frequent but brief
trips to the water water cooler or restroom to give our eyes a break. In restroom,
don’t look directly at the fluorescent lights overhead because it will only cause
more strain.
Enlarge text:
Our eyes have to strain to read small text, so keep text large to give your
eyes a break. Always magnify to a size that feels comfortable. Print out large
documents and read it at your own pace and in the right lighting.
Re-position your monitor:
When we stare at computer monitor, we naturally blink less often. So our
eyes don’t get naturally lubricated as often. This leads to eye dryness and
redness. To reduce this effect, position the monitor below eye-level. By this,
eyes won’t have to strain in order to see. Even if our monitor settings are set
for optimal usage, light from the surrounding can irritate the eyes. Consider
using an anti-glare screen if necessary. And position desk lights at an angle
from behind.

7. Eyes wide shut.
Our best advice to people who work at computers all day is to close your
eyes often--that is, blink a lot! Dry eyes can make you feel tired, and blinking
keeps them lubricated and moist. If blinking alone doesn't help, use eye drops
for additional moisture.
Relax:
Work is important, but you need to be relaxed enough so that tension and
stress don’t get in the way. Take frequent short breaks during the day, and
longer breaks one to two times a day so that you can get your mind off work.
Walks are good because give you exercise, fresh air, and help you look off into
farther distances.At your desk you can do neck rolls, shoulder shrugs and arm
swings to stretch out your neck and shoulders. Rub your temples to release any
head tension. Give your eyes periods of darkness for rest, by closing your eyes
or cupping your palms over your eyes (preferably in a quiet environment).

8. Neck and shoulder basics
• Glare spots reflected off the screen or direct light shining in your eyes can
cause you to bend or lean in weird positions. This increases neck tension.
• If your documents are flat on the desk and to the side of the keyboard you
are bending and twisting the neck. Think drafting table; place your
documents up on an angle to straighten the neck, place them near the
monitor to limit twisting.
• Reaching to the mouse, keyboard, or other supplies can cause strain.
Working with the arm extended and unsupported can increases shoulder

9. strain as much as 7 to 10 times. Place frequently-used items closer or find
a place to support the arm.
• If your Keyboard is too high you are probably working with tense
shrugged shoulders. We recommend placing the keyboard relatively low,
near your resting elbow height.
• Elbows winged out to the side to reach for the arm rests? This can cause
considerable strain to the shoulder muscles. See if the armrests can be
adjusted in closer, or try working without using the armrests. Moving the
arm out to use the mouse can over-work the small rotator cuff muscle in
the upper shoulder blade. Consider a narrower keyboard or keyboard
without a number pad to allow closer mouse placement, or a central
pointing device.
Some Posture Guidelines
• Let your shoulders relax.
• Let your elbows swing free.
• Keep your wrists straight.
• Pull your chin in to look down - don't flop your head forward.
• Keep the hollow in the base of your spine.
• Try leaning back in the chair.
• Don't slouch or slump forward.
• Alter your posture from time to time.
• Every 20 minutes, get up and bend your spine backward.
• For reducing inflammation and pain: Try ice or a package of frozen
vegetables (like peas) on the affected area.
• Thighs and feet should rest parallel to the floor. If you can't adjust
your seat, use a special footrest with a nonslip surface. And clean up
that mess: Make sure your have room under your desk to stretch your
legs.