An applied science concerned with designing and arranging things people use so that the people and things interact most efficiently and safely -- called also human engineering.

Part of making our workplace, and more increasingly our homes, a safer, more user-friendly environment involves establishing good habits as far as utilizing our bodies correctly and using furniture and equipment that facilitates us to do so.

The following will review the primary risk factors and solutions involved in the science of Ergonomics.

Ergonomic and medical experts have identified four key risk factors associated with complaints of discomfort in the work environment: awkward postures, bio-mechanical stresses, repetitions and force.

Given these risk factors as they relate to those who use computers or sit for long periods of time, the key is to eliminate the risk by providing a well-designed environment.

The following will outline each topic, explain the risks associated and will help in deciding the best solutions or prevention for each.

Awkward posture
The first risk factor, awkward posture, has to do with how the human body is positioned throughout the day. This is probably the most significant risks in an office environment. Often, a ridged, strained image comes to mind, such as holding a book on the head. Instead, try thinking of posture as the most efficient way for a body to be positioned, or to move, depending on the demands of the situation.

The human body is well designed for a large variety of movements and postures. However, each joint (like the knee) or series of joints (like the spine), has a so-called "neutral" position or posture. In this position, the surfaces of the joint and the tissues around it are neither over-stretched nor compressed.

Seating
Ergonomic products should support the body’s natural postures. A chair, for example, that forces the spine to change out of its natural "S" shape is not ergonomically designed. Most office seating now has a molded shape that supports the curvature of most spines.

Brodart offers only quality-upholstered chairs and stools that provide proper support.
Beware of low cost task chairs that do not offer this.

Good office ergonomics with regard to posture, however, does not only mean seating.

One postural risk factor is excessive or prolonged positioning of the head away from its "neutral" position. While working at the keyboard and anytime while sitting in one position for a long time (on the phone, reading, writing, watching TV, driving, etc.) keep the head as straight as possible with the ears lined up over the shoulders. Sometimes, the desk surface on which the monitor sits provides for height adjustments of the monitor. If not, a monitor stand, ranging from a simple, stable surface on which to place the monitor at a better height to an adjustable arm can be used.

Shoulder & Back Positioning
Awkward posture can also affect the upper torso. The shoulder and upper back are "at rest," or in a neutral posture, when the shoulders are in line with the body and the arms are by one’s sides.

Take a deep breath, sigh, and let your body relax. This is a neutral position. If the shoulders are held in a rounded or slumped position, or if the arms are held away from the body in any direction for a length of time, the upper back and shoulder muscles may fatigue and eventually get sore.

To assist in preventing discomfort, change positions frequently throughout the day and return to the "straight shoulder position," with arms, wrists and hands by one’s sides, as much as possible.

Research has shown that the muscles around the elbow function best when the elbow is bent to about 90 degrees (give or take about 10 degrees), depending on the activity. Holding the elbows too bent or too straight can cause fatigue in these muscles. That is why adjustable, soft armrests on office seating and adjustable-height, articulating keyboard trays are a good idea.

See our wide selection of keyboard pullouts that can be added to any computer workstation or tables. Several models of keyboard pullout do not require any tools or a permanent attachment.

Most of the muscles that move the wrist and the fingers located in the forearm, with their long tendons (connective tissue that connects muscles to bone) crossing the wrist area. On the palm side, nine finger tendons and a major nerve (median nerve) go through a passageway called the carpal tunnel. The back of the tunnel is made up of wrist bones, and the front of the tunnel is comprised of a thick band of connective tissue.

The carpal tunnel is largest when the wrist is straight; this is the neutral position for the wrist. When the wrist is bent too far, whether forward or backward, the tissues in the tunnel may be compressed or pinched. Imagine them as a garden hose, which cannot function, well when bent at an angle or squished. Therefore, it is important to keep the wrist fairly straight when using the hands.

The primary cause of poor wrist postures in an office environment is the use of a keyboard or other input device such as a mouse, trackball or touch pad. It is important to select input devices based on you needs, the tasks that you perform and the configuration of their workstation.

For example, the best keyboard for most people is the standard QWERTY keyboard that comes with most computers. The keyboard layout allows most users to key without causing the wrists to deviate from one side or the other.

The wrist should be straight as if you drew an imaginary line through the center of the elbow extending it through the wrists and fingertips. This imaginary line should be parallel to the floor. The keyboard tray should clear the legs and be at a height keeping the forearms parallel to the floor.

Wrist rests come in a variety of materials (foam and gel), with no major difference other than personal preference for feel.

Individuals should experiment and decide with which wrist rests they are most comfortable.

Individuals experiencing mild symptoms of discomfort and fatigue in their arms or hands should probably try using a wrist rest and note any changes. (Any questions about the causes or treatments of such symptoms should be referred to a health professional.).

Spinal Column/Lumbar Section
The spinal column is not straight. In its neutral position, it has three curves balanced over on another; one going in at the neck, out at the shoulders and ribs, and in again at the low back behind your stomach. An exaggeration of these curves in either direction can cause problems, especially if the posture is maintained for a long period of time.

In particular, when you slouch forward and round the back, the muscles can no longer support them and they are "hanging" on their ligaments. This may feel fine for brief periods of time, but prolonged slouching puts strain on the back ligaments, which can over-stretch them and lead to fatigue and backache.

Slouching also compresses the internal organs and could interfere with their function. In the long term, it is much better for the back if pressure is taken off the ligaments by sitting up straight in the chair.

Ideally, support for the lumbar spine should come from the chair itself. All newer ergonomically designed chairs have varying degrees of such support built into the chair.

It is appropriate to first check the fit and adjustments of the chair if an individual has questions about lumbar support. Ensure that any chair you evaluate allows the height of the backrest to be adjusted for desired support. Specifying a chair with forward, backward and seat angle adjustments can affect the amount of support and comfort the chair provides.

Keep weight evenly distributed on the buttocks with the hips and knees at about a 90-degree, or "L" angle. Good sitting posture is obtained when the ears, shoulders and hips are aligned. This keeps the natural back curves safely balanced.

Furniture Adjustment
One of the easiest ways to adjust the furniture is to sit in the chair while bending the elbows to the "L," or 90-degrees, position with the arms directly at one’s sides and the wrists straight. Then slide up to the keyboard. All of the fingers should touch the keys without having to change position and the feet should touch the floor. Then the keyboard is at a good height. If not, adjust the seat height and try again. If the keyboard height is adjustable, adjust it to reach the hands without changing the arm position.

Next, check the position of the legs and feet. The legs should be supported and the thighs approximately parallel to the floor. This helps keep the hips and knees at a 90-degree angle.

If you have raised the chair and the feet no longer touch the floor, a footrest can be used to "bring the floor to you." Or, you

May prefer a footrest. Use a footrest with a nonskid surface, and one that is heavy enough to remain stationary and large enough to accommodate both feet.

The chair should assist in maintaining good posture. When performing typical office tasks, you should be able to sit back into the chair and allow it to provide support. Office task seating comes in different sizes for a diverse work force and has different features that can be adjusted to meet an individual’s needs.

One final important note on posture: no one can, nor should, sit in one position, even a correct one, for the entire day. It is critical to change positions frequently to allow blood flow and nutrients to the muscles. Postural adjustments do not have to be drastic.

You should return to the recommended posture as much as possible throughout the day. In the short term, it might feel hard to avoid slouching. Keep in mind that this may be due to weak muscles. If that is the case, you should sit in the recommended posture for as long as you can, and then return to it often throughout the day. Gradually, you will be able to maintain better posture for longer periods as the muscles get stronger.

The most important purpose of the chair is to provide stability for the body at work and to assist in the maintenance of neutral body postures. For the all-day user, the chair also might provide options for mobility or alternative positions.

Comfort in a chair is an individual and relative state. The chair should feel reasonably comfortable given its purpose of support. Keep in mind, for example, that a soft slipper might feel comfortable on the feet but would not give the user appropriate support for all day wear.

Monitor Heights
One should be able to view the screen without bending the neck forward or to the side. If the neck is being bent, try raising or lowering the monitor to find a better position. In some cases, raising or lowering the chair may help in this process.

A good rule of thumb for a starting point is to line up the menu bar on the screen with the eyes. Also, if the screen tilts, try tilting it very slightly downward, as the normal visual gaze is slightly downward. This can help to prevent the screen from reflecting overhead light.

Keep in mind, however, that these recommendations often vary with individual visual needs (for example, the use of bifocals), as well as the type of job being done. The primary goal is to maintain a healthy posture for the head and neck. Some experimentation may be necessary. We have a variety of monitor stands in all sizes and styles to ensure that you find the model that’s best for you.

Document Holder
While keying, try to avoid constantly bending the neck and head down to look at the keys or documents. If looking down is necessary, try to look down with the eyes while keeping the neck fairly straight. To avoid turning the head to one side for long periods of time, evaluate the placement of any documents and bring them as close to the monitor as possible.

The best solution to solving this problem can be a document or copy holder to hold materials in the proper placement. Objects and materials used frequently should be kept within a comfortable reaching distance. Again, different jobs may call for different styles of document holders. For example, if writing tasks are required, a heavier, fixed document platform may be necessary.

Because we are all individuals, it is important to take the time to adjust workstations to fit your situation.

Workstation Component Design & Mechanical Stresses
The next factor for discomfort has to do with problems that can occur where the work equipment contacts the human body.

For video display terminal (VDT) users, the first main area for potential contact is at the wrist. When keying, if the wrists rest on a table edge, there may be prolonged mechanical stress on that area.

The lips on pullout keyboard drawers are usually rounded and generally give adequate support, but some people may prefer to use a soft, contoured wrist rest for additional padding and support.

The same mechanical stresses found on the sharp edge of a workstation can increase pressure on anther nerve in the forearm or elbow area if you push back the keyboard and lean on the table. Because this nerve is close to the elbow (this is what reacts when hit your funny bone), it is wise to avoid prolonged resting of the elbows on any hard surface, be it an arm rest, table top, etc.

The last potential area of mechanical stress is the front edge of the chair seat. If the feet dangle or are hooked around the chair supports, circulation may decrease to the legs and feet. More and more chairs now have a "waterfall" front edge, which helps to decrease their pressure. For those whose chair will not get low enough so that feet rest flat on the floor, a footstool may be a temporary solution to remove pressure off the back of the thighs.

Reducing Force and Repetition
How you key is as important as where you key. The last two risk factors, force and repetition, involve keying techniques. Force should not be a problem for VDT users, as force required for a keystroke is quite small. Some individuals, however, consistently hit the keys with unnecessary force as they work. This can put excessive strain on the small finger muscles and tendons, so remember to key lightly. Select keyboards and other input devices based on "feel." This may be appropriate when specifying a keyboard for someone who has already had an injury.

The other risk factor is repetition. Keyboard use by its very nature requires repetitive use of the hands. Some people, however, habitually bend their wrists away from the neutral position while keying. This is strongly discouraged because it can unnecessarily fatigue the wrist muscles and tendons. The wrist should be kept straight and still while keying, and the arms moved slightly to reach the keys, if necessary, instead of the wrists.

Eyestrain
One other common problem for video display terminal (VDT) users is eyestrain. Every day, our eyes are constantly responding to the demands we place upon them; focusing and refocusing through the action of very small muscles within the eyes. As the eyes age their ability to focus decreases slowly over time and a person’s comfortable focus point moves farther away. This change usually begins in the mid-20s, so at each age, there might be a different comfortable viewing distance for an individual.

In addition, a large percentage of the "normal" adult population has corrected vision conditions. The intensity of any visually demanding job or lifestyle, including VDT usage, can certainly bring such conditions to our attention.

For all of these reasons, you should have regular visual checkups. It is important to tell the doctor that if work at a VDT, how much time you spend at it daily, what the light source is, what type of light to which you are exposed and the approximate distance from the screen you tend to sit.

Screen Glare
Glare, or what more appropriately should be called nuisance lighting, on the monitor screen can also be a problem. This causes the eyes to make unconscious adjustments to the reflections. Minimizing or eliminating glare is important and can be done in several ways.

First, just raising, lowering or turning a monitor slightly can do a lot to decrease glare. Next, check for items that cause reflective glare in the field of vision (such as task lighting, glass picture frames, large pieces of jewelry, etc.) and move such objects. Window coverings (blinds, curtains, etc.) may need to be adjusted throughout the day as the light changes. Often, however, screen-filters are necessary to reduce the glare. Features which appear on some styles of computer screen-filters are: privacy, anti-static, or magnifying filters.