Computer Operators' Risk Factors

Ergonomics is the scientific, interdisciplinary study of individuals and their physical relationship to the work environment.

Many activities and work operations can cause minor aches and pains that we all experience at one time or another. For those who spend large amounts of time working with computer workstations, however, three factors have been identified as contributing to ergonomically related problems.

Although any one alone can create problems, the combination of all three produces the most significant risk of injury. While reviewing these factors, keep in mind that they apply to all activities, and not just computer use at work. Also, recognize that you have control over how you work, and that your approach to the work can have a significant impact in preventing future problems.

Awkward Positions

Body postures determine which joints and muscles are used in an activity, as well as the amount of force exerted. Poor postures place unusual or excessive forces on components of the body. Examples of poor positions include keeping a computer mouse far from the keyboard or not locating the keyboard and monitor in a straight line from your seat. These kinds of awkward positions create undue stresses at the wrists, shoulders, and neck.


This refers to the amount of time a person holds a static position to perform a given task. The longer the same muscle or muscle group is used, the greater the likelihood of both localized and general fatigue. This is why rest breaks or changing tasks is so important to decrease prolonged static postures and thereby reduce the risk of injury. Also important is the use of position aides—such as foot rests, copy holders, adjustable chairs, and keyboard trays—to minimize fatigue to muscle groups not directly involved in the computer work activity.

Repetitive Motions

Motions performed only infrequently, even if performed in an awkward position, seldom result in any bodily harm. However, as a particular motion becomes more and more frequent, the risk of injury increases. With keyboard work, some motions are repeated as often as every few seconds, and some even faster. When performed for prolonged periods, e.g., hours without a break, fatigue and strains accumulate. Changing tasks during the day, or taking periodic breaks, can provide muscles and tendons with the time needed to recover to their normal, unstressed state.

It is very important for you to be aware of risk factors that can lead to potential work related musculoskeletal problems. Awareness of these risks can help you to avoid discomfort and injury when using a computer.

Risk Factors

Tips to Reduce Risk

  • Alternate tasks.
  • Take frequent breaks from keying/or mousing.
  • Sit supported against the back of your chair.
  • Avoid bending or twisting your neck or trunk.
  • Keep your shoulders relaxed and arms close to your sides when working.
  • Keep your elbows at a 100- to 110-degree angle when using the keyboard and mouse.
  • Keep your wrist in a straight or neutral position when keying or mousing.
  • Keep your fingers in a relaxed position when keying or using the mouse.
  • Keep work materials within close reach.
  • Use a telephone headset for frequent/prolonged phone use.
  • Change positions/tasks frequently.
  • Key with a light touch.
  • Avoid prolonged or excessive grasping of the mouse
  • Use larger diameter pens to reduce grip when writing.
  • Use electric stapler for large jobs.
  • Avoid resting weight on elbows on the edge or surface of a table.
  • Reduce glare on your computer screen by adjusting its placement and tilt, using a glare guard or using window blinds and light filters.
  • Rest eyes intermittently by focusing on distant objects.
  • Take visual breaks.
  • Remember to blink often when viewing the monitor