continual or recurring discomfort
aches and pains
throbbing
tingling
numbness
burning sensation
or stiffness
Seek help even if symptoms occur when you are not working at your computer.
Laptop computers can present particular problems due to small screens, keyboards and inbuilt pointing devices (e.g. a small portable mouse or touchpad). Prolonged use of laptops should be avoided. If using a laptop as a main computer (i.e. use as a normal desktop computer in addition to use as a portable), it is advisable to use the laptop with a docking station. This allows an ordinary mouse, keyboard and monitor to be used with the laptop. The main risks associated with using computers include:
Musculoskeletal problems
Eye strain and a greater awareness of existing eye problems
Rashes and other skin complaints have also been reported, although it is thought these are caused by the dry atmosphere and static electricity associated with display units rather then by the display units themselves. There are potential risks from radiation though this is a contentious area.
Musculoskeletal problems
These can range from general aches and pains to more serious problems and include:
Upper limb disorders such as repetitive strain injury (RSI) tenosynovitis and carpal tunnel syndrome - by far the most important as it can quickly lead to permanent incapacity
Back and neck pain and discomfort
Tension stress headaches and related ailments
These types of problem can be caused by:
Maintaining an unnatural or unhealthy posture while using the computer
Inadequate lower back support
Sitting in the same position for an extended period of time
An ergonomically poor workstation set up
Eye strain
Computer users can experience a number of symptoms related to vision including:
Visual fatigue
Blurred or double vision
Burning and watering eyes
Headaches and frequent changes in prescription glasses
Computer work hasn't been proven to cause permanent eye damage, but the temporary discomfort that may occur can reduce productivity, cause lost work time and reduce job satisfaction. Eye problems are usually the result of visual fatigue or glare from bright windows or strong light sources, light reflecting off the display screen or poor display screen contrast.
Prevention is better than cure
Several relatively straightforward precautions can be taken by computer users to avoid problems.
Avoiding Musculoskeletal problems
General precautions to avoid musculoskeletal problems include:
Taking regular breaks from working at your computer - a few minutes at least once an hour
Alternating work tasks
Regular stretching to relax your body
Using equipment such as footrests, wrist rests and document holders if you need to
Keeping your mouse and keyboard at the same level
Avoiding gripping your mouse too tightly - hold the mouse lightly and click gently
Familiarise yourself with keyboard shortcuts for applications you regularly use (to avoid overusing the mouse)
It is also important to have your workstation set up correctly. Your workstation includes monitor, keyboard, mouse, seating, desk, and where appropriate, footrest (to enable you to put your feet flat if they would otherwise not reach the floor), wrist rest, and document holder. Monitors should:
Swivel, tilt and elevate - if not use an adjustable stand, books or blocks adjust the height
Be positioned so the top line of the monitor is no higher than your eyes or no lower than 20° below the horizon of your eyes or field of vision
Be at the same level and beside the document holder if you use one
Be between 18 to 24 inches away from your face
Keyboards should:
Be detachable and adjustable (with legs to adjust angle)
Allow your forearms to be parallel to the floor without raising your elbows
Allow your wrists to be in line with your forearms so your wrists does not need to be flexed up or down
Include enough space to rest your wrists or should include a padded detachable wrist rest (or you can use a separate gel wrist rest which should be at least 50 mm deep)
Be placed directly in front of the monitor and at the same height as the mouse, track ball or touch pad
Chairs should:
Support the back - and have a vertically adjustable independent back rest that returns to its original position and has tilt adjustment to support the lower back
Allow chair height to be adjusted from a sitting position
Be adjusted so the back crease of the knee is slightly higher than the pan of the chair (use a suitable footrest where necessary)
Be supported by a five prong caster base
Have removable and adjustable armrests
Have a contoured seat with breathable fabric and rounded edges to distribute the weight and should be adjustable to allow the seat pan to tilt forward or back
Tables and desks should:
Provide sufficient leg room and preferably be height adjustable
Have enough room to support the computer equipment and space for documents
Be at least 900 mm deep
Have rounded corners and edges
Avoiding Eyestrain
Precautions that can be taken to avoid eyestrain include:
Exercising the eyes by periodically focusing on objects at varying distances
Blinking regularly
Keeping the air around you moist - for example using plants, open pans of water or a humidifier (spider plants are said to be particularly good for this and removing chemical vapours from the air)
Adjusting the screen height / seating so that when sitting comfortably your eyes are in line with the top of the monitor screen
Adjusting the brightness control on your monitor for comfort
Adjusting the contrast on your monitor to make the characters distinct from the background
Adjusting the refresh rate of your monitor to stop it flickering
Positioning monitors to avoid glare (e.g. not directly in front of windows)
Keeping your monitor the screen clean
Keeping the screen and document holder (if you use one) at the same distance from your eyes
Servicing, repairing or replacing monitors that flicker or have inadequate clarity
Regular eye testing - do this at least once every 2 years and more frequently if necessary - especially if you are experiencing eye problems related to using display equipment. Indicate the distance from your eyes to the monitor to your optician and talk to them regarding special lenses or the use of bifocals.