North Seattle Community
College
Computer
Workstation
Ergonomics
WORKSHOP OUTLINE
• Understand the definition of
ergonomics
• Understand Primary Causes of
Cumulative Trauma Disorders
(CTDs).
• Understand ways to prevent
CTDs
• Learn about PC workstation
setup and accessories to reduce
computer work stress
• Basic exercises to reduce /
relieve ergo-stress.
DEFINITION
• ERGONOMICS is a way
to work smarter--not
harder by designing of
tools, equipment, work
stations and tasks to fit the
job to the worker--NOT
the worker to the job:
– Layout
– Lighting &
Temperature
– Process
WHY WORRY ?
• Work Related Musculoskeletal
Disorders (WMSDs) are fastestgrowing injury/illness category
(accounting for over 1.8 million annual
lost workday cases in 1997 BLS stats).
• Up 600% over last 11 years
• $13 to 20 billion total injury cost / year
& average $29 K / case compensation
claim cost
• More lost workdays for RSIs (ave. =
30 days for a Carpal Tunnel injury)
MSD INJURY DATA
• 600,000 MSDs require
time off from work.
• Women suffer more
ergonomic injuries
due:
– to having jobs
requiring more heavy
lifting, repetitive tasks
and awkward postures
– 70% of Carpal Tunnel
– 62% of Tendonitis
CTD INJURY FACTORS
• Lesions to tendons of
the neck, back,
shoulders, arms, wrists
or hands
• Primary causes:
– Repetitive
movements over
long periods of time
– Awkward postures
– Use of excessive
forces
CTD RISK CONTROL:
POSTURE
• NEUTRAL &
COMFORTABLE:
– Wrists straight
– Shoulders relaxed with
elbows close to body
– head / shoulders &
back in vertical
alignment
– Frequent breaks
especially when bent
postures can’t be
avoided
CARPAL TUNNEL SYNDROME
• Occurs with repetitive motion of hands & wrists-especially with high force levels.
• Incidence up to 15% in certain industries.
• Good posture, wrist support and a “natural”
keyboard can help most PC users avoid problems
• GOOD NEWS: Have dropped about 30% since
1990--which most attribute to strong workplace
ergonomics programs
CTD RISK CONTROL:
REPETITION
• Eliminate unnecessary
tasks / movements by
redesigning workstations
• Take short, frequent
breaks
• Alternate tasks and
processes to use different
muscle groups
Computer Ergonomics
•
•
•
•
Routine PC user defined as spending 20
hours or more per week working at a
computer.
Studies of PC users have not shown a risk
of eye damage...although fatigue very
possible.
NIOSH studies have not indicated a
radiation hazard nor pregnancy risk from
PC usage.
Workers using bi/tri-focal glasses before
beginning PC use may want to consider
purchasing special purpose glasses for
computer work.
“NATURAL” KEYBOARDS
• Three types: Fixed split, Adjustable split &
“Sculptured”
• Awkward wrist postures minimized with 15
to 25 horizontal degree key split AND 8 to
66 degree vertical incline.
• Key Layout Design Changes Have:
– increased comfort (81% of users)
– improved postures
– reduced muscle activity
– lowered carpal tunnel pressure in lab
settings
• Obtained primarily to alleviate an injury
WRIST RESTS
• No medical evidence that they reduce RSI injuries...As
they work for some, but not for others
• Usage Guidelines:
– Buy rest that is even with top of keyboard
– Material should be “medium-soft” (foam--gel mix) so foam
doesn’t break down. AVOID hard plastic types
– DON’T leave wrists on rest...which compresses carpal
tunnel. Palm rest instead.
– Changing typing habits more critical than wrist support
– MOST APPROPRIATELY USED TO REST HANDS
DURING PAUSE IN TYPING
• LEARN TO TYPE CORRECTLY WITH
“FLOATING WRISTS” FIRST!!!
Monitor and keyboard position
•
•
•
•
•
THE KEYBOARD AND
MONITOR SHOULD BE
DIRECTLY IN FRONT OF THE
USER
THE TOP OF THE MONITOR
SHOULD BE AT EYE LEVEL TO
AVOID NECK STRAIN
THE USER’S ELBOWS SHOULD
BE BENT AT A 90+ degree
ANGLE
THE FRONT EDGE OF THE
KEYBOARD SHOULD BE
SLIGHTLY ELEVATED TO
ALLOW THE USER’S WRISTS
TO BE IN A NEUTRAL
POSITION
THE SCREEN SHOULD BE
POSITIONED AT RIGHT
ANGLES TO THE WINDOW TO
AVOID GLARE
Ergonomic chairs
• Adjustable back height
– lumbar support
• Adjustable arm rests
• Adjustable seat pan
height and depth
• **Chair on left NOT
ergonomically
designed
Alternative Pointing Devices
• Track-balls
• “Scrolling” Mouse
• Laser Mouse
Other Ergonomic PC Accessories
• Height-adjustable articulating keyboard tray - $49
https://www.buymicro.com/secure/default.cfm?itm_
code=120917&src=4
PC Station “Design”
PC Station “Design”
MODEL COMPUTER WORKSTATION
• --Keyboard trays WITH wrist
support.
• --Split "Natural" keyboards
to facilitate neutral wrist
angle
• --Fully adjustable
ergonomic chair
• --Document holder (ideally
same height as monitor) to
minimize head / eye & neck
movements
• --Corner desk units to
position monitor directly
in front of employee
• --Foot rest where required
• --Re-organization of
Good Posture
• In general keep your head
balanced over shoulders -looking forward.
• Shoulders relaxed and
comfortable.
• Wrists straight.
• Lower back supported
(don't slouch).
• Feet settled on floor or
footrest.
• Forearms/Thighs parallel
to floor – may need to
adjust from time to time.
ERGONOMICS SUMMARY
• Good ergonomic design of your
workstation DOES improve
personnel comfort, health,
morale and productivity.
• Individual awareness is one of
the greatest means of
identifying / improving
workplace ergonomic issues.
• It’s critical to seek prompt
medical aid for symptoms of
ergonomic stress / CTDs
Desk Stretches
• Stretch breaks help reduce
muscle tension caused when
muscles remain static or fixed
in one position for too long.
• Muscles when remaining static
will fatigue more easily,
circulation will decrease, you
will become uncomfortable and
the task will become more
difficult
• Stretching can help relieve
discomfort due to repetitive
movements, awkward postures,
and excessive force.
Desk Stretches
• The following exercises are
examples you can try. If you are
already experiencing CTD
(RSI) or have experienced other
medical problems, seek advice
from your doctor before
beginning these stretches.
• Remember to start out easy and
stretch regularly. Hold the
stretch 5 to 10 seconds.
• http://keats.admin.virginia.edu/e
rgo/stretch.html
• http://www.mydailyyoga.com/y
oga/rsi.html