Office Health and Safety: Ergonomics
Poor ergonomic conditions exist when the work is incompatible with the workers' bodies and their ability to continue working.
Work-related musculo-skeletal disorders (WMSD) are the most commonly occurring hazards in modern offices. These injuries result from poorly designed workstations, and inadequate job design. Two common types of WMSD are muscular strain in the neck, shoulders and back, due to prolonged sitting; and injury to joints and muscles due to excessive repetition of movements.
Ergonomics deals with the compatibility between workers and their work. "Work" is made up of the work environment, workstations, and tasks. Poor ergonomic conditions exist when the "work" is incompatible with the workers' bodies and their ability to continue working. Such conditions may cause discomfort, fatigue and pain and, subsequently, injury. Injuries resulting from poor ergonomic conditions are collectively known as musculo-skeletal injuries (MSI), repetitive strain injuries (RSI) or repetitive motion injuries (RMI) or work-related musculo-skeletal disorders (WMSD). The causes of these injuries are prolonged work involving repetitive movements, forceful movements and awkward body postures. WMSD are painful and often disabling injuries which affect mainly the wrists, back, legs, shoulders, neck, muscles and joints.
Adequate environmental conditions are important for the overall well-being of workers and productivity. When the work area is too cold or too hot, poorly lit, noisy, poorly ventilated, or contains unpleasant odours it results in annoyance, stress, fatigue, eye strain, headache and other conditions. Injuries and illnesses related to poor ergonomic conditions can be prevented by making the workplace and the work organization fit the physical and mental ability of each individual worker.
Below is a summary of some of the common ergonomic hazards in the office and their impacts on the workers.
Performing the same or similar motions repeatedly can result in trauma to the joints and surrounding tissues. Without time for rest and recovery, repetition can lead to injury.
Examples of repetitive motions include typing at the computer keyboard, flipping through files and paperwork, moving and clicking the mouse, using a calculator, looking back and forth between the monitor and source documents, writing by hand, stapling and three-hole punching by hand.
Static loading or sustained exertions
One of the risk factors that has increased in the computerized office is static loading, where the muscles must hold the body in a single position for a long period of time. This lack of movement reduces circulation and causes muscle tension, which can contribute to or aggravate an injury. Sustained exertions are a type of static loading where force is applied continuously for long periods of time.
Work that requires holding the hands in place above the keyboard or mouse, holding down the Shift key, sitting upright without back support, holding the handset while talking on the telephone, sitting still for long periods of time or even holding boxes in the hands while carrying them long distances expopses the worker to static loading.
Postures that bend the joints into positions where they are more likely to become injured are termed awkward postures. These include typing with bent wrists, slouching or leaning forward in the chair, turning the head to the side to view the monitor, cradling the phone between the ear and the shoulder, elevating the arms when writing on a work surface that is too high or bending at the waist to load copy machines.
Mechanical contact stress
Mechanical contact stress comes as a result of a hard or sharp surface or object pressing into the soft tissues; the tendons, nerves and blood vessels and can cause damage that over time can result in serious injury.
Examples of mechanical contact stress include resting wrists on the desk edge while typing or using the mouse, using rubber stamps with handles that press into the palm of the hand, leaning the elbows on hard chair armrests or work surfaces, using scissors with hard, metal handles, sitting in a chair that places pressure on the backs of the thighs, etc.
Many office tasks require a moderate amount of force to be applied by very small muscles, which may cause fatigue, swelling, muscle strains and ligament strains. These tasks include "dragging and dropping" with the mouse, grasping thick file folders or manuals, gripping the sides of the mouse tightly, stapling or stamping by hand, "pounding" on the keyboard and lifting heavy manuals with one hand.
In addition, there is still the occasional need to lift items such as computer equipment and boxes of copy paper or files. Most office workers are not trained in proper lifting techniques. Also, seated work tends to weaken the stomach muscles, which would ordinarily help support the spine when lifting. Both of these factors place office workers at a greater risk for injury, even from the occasional lift.
The first step in implementing ergonomics in the office is to analyze the work being done, whether you are looking at a single workstation or the entire department. A careful analysis will help to identify the true cause of the problem and to apply the appropriate resources. Many times the analysis may reveal that only small changes are necessary, in which case a more involved analysis may not be necessary. Other times, more complex problems that will require evaluation by an experienced professional may be identified. Most of the time, however, it is likely that the problems can be resolved with the help of the employees in the area and the resources at hand.