“Conventional Wisdom” vs. Current Ergonomics Thinking 16 common ergonomic practices are put to the test. See which ones are old wives tales and which are sound advice.
Being Effective; You have to know how to get things done. To be blunt about it, if you can’t answer these thirteen questions, you may never manage to help anybody.
This page summarizes some of the new research in office ergonomics and presents some new ways of working.
Most of us have some misinformation about office setup and posture. Much of the misinformation is quite old, but it persists because:
- We’ve heard it all our lives.
- Everybody we know seems to think the same thing,
- It sort of makes mechanical sense (but not biological sense!),
- We actually heard or saw it RECENTLY, perhaps in a sales presentation for some kind of ergo gizmo.
Unfortunately, not all writers, trainers, product designers, or even physicians can keep up with all the scientific developments. Here are examples of conventional ergonomic wisdom that are being disproven. Most of them involve, happily, a RELAXING of old strict rules. Current ergonomics encourages variety and movement rather than an exact posture.
“Conventional Wisdom” vs. Current Ergonomics Thinking
1. Conventional wisdom for monitor distance is that it should be 18-24 inches away. This is wrong. The best distance is “as far away as possible while still being able to read it clearly.” Longer distances relax the eyes. The “conventional” 18-24 inch recommendation is unnecessarily close. For more on this, see the Eyestrain and Neck Pain link above.
2. Conventional wisdom for keyboard distance is that it should be approximately at the front of the work surface. This conventional wisdom is limiting. There’s nothing wrong with pushing the keyboard back farther if the forearms are supported, provided the wrist is kept straight and the elbows aren’t resting on anything hard or sharp. Usually, to make a pushed-back keyboard work, the worksurface should be higher than elbow height. (see height, below)
3. Conventional practice for placement of the mouse is to push it away. Closer is usually better — next to the keyboard is the goal.
4. Conventional wisdom regarding a chair is that the chair should be at a height that allows the feet to reach the floor when the legs are in the “conventional wisdom” position of 90 degrees (at the knee). The ninety-degree knee posture is not “correct” ergonomics although it is not a harmful position. The legs should move very often, not stay fixed in the ninety degree position. The chair should, if possible, be low — low enough for the feet to rest on the floor, even when extended.
However, if the chair is at a good height but the keyboard height can’t be adjusted to elbow height or lower, then it’s necessary to adjust the chair upwards. In this case, a footrest is an option.
5. Conventional wisdom says footrests are always a fine alternative and that chairs and worksurfaces don’t need to be lowered if a footrest is available. The truth is that footrests are a distinctly second-class choice because the feet only have one place to be, and leg postures are limited.
However, if the chair is already low enough, footrests offer a chance to change leg postures and are recommended.
6. Conventional wisdom prescribes an upright posture, with the hips at ninety degrees. However, a great deal of research supports the idea of a much wider hip angle — with one hundred thirty degrees or so as an “optimum” angle. The reason? When the hips are straightened, the vertebrae of the lower spine are aligned with each other in a way that reduces and evens out pressure on the intervertebral discs. Further, sitting upright is less desirable than reclining. When reclining, the lower back muscles work less and the spine supports less weight, since body weight is held up by the chair’s backrest.
7. Conventional wisdom for keyboard height is that it should be at elbow height. This is wrong, or at least too narrow. Variation from elbow height is fine, especially in the lower-than-elbow direction.
8. Conventional wisdom for keyboard angle is that it should be flat, or up on its little support legs. This is wrong. The keyboard angle depends entirely on the forearm angle, and should be in the same plane as the forearm. So, a low keyboard should be slanted back. Some people expect they won’t be able to see the keys if the keyboard is sloped back, but this is usually not a problem.
9. Conventional wisdom is that the wrists should be kept straight. In this case, conventional wisdom is correct, as far as we now know.
10. Conventional wisdom for monitor height is that the top of the screen should be about at eye height. This is fine for some people, wrong for many. The current recommendation is that eye height is the highest a monitor should be, not the best height. Many people find a low monitor to be more comfortable for the eyes and neck.
Conventional practice puts the monitor on top of the CPU — the best solution in most cases is to put the monitor on the work surface, because of the monitor height issue.
11. Conventional wisdom for wrist rests is that they can do no wrong and should always be used. This is wrong. They may be able to cause harm if they’re too thick, too thin, too hard, or have sharp edges (even sharp edges of foam). They also can cause harm, we think, if they’re constantly used — they probably should be used just during pauses. The carpal tunnel is under the wrist/palm and should not be subjected to much extra pressure.
12. Conventional practice is to supply wrist rests for the keyboard but not the mouse. Mouse wrist rests are a good idea in many cases, but the same warnings apply.
13. Conventional wisdom for “ergonomic” keyboards is that they’re good for everybody. In actuality, some are good and some are probably bad. Some are right for some people and not for others. The only kind of ergonomic keyboard that many ergonomists can recommend in good conscience is one that can be configured to look exactly like a normal keyboard. These boards are hinged and can be changed to a new shape gradually. See our Ergo Products Buyers Guide to the left more about ergonomic keyboards.
14. Conventional practice recommends rest breaks about fifteen minutes long, every two hours or so. This is insufficient for single-task work such as typing. Research supports the idea of very short breaks done very frequently — for example, 30-second breaks every ten minutes or so. These should happen in addition to the normal fifteen-minute coffee breaks.
15. Conventional wisdom for computer and peripheral arrangement is for the keyboard and monitor to be aligned directly in front of the user, and for note pads and documents to be placed to the side. This is wrong for all those computer users who spend more time reading/ writing and tracking the document. For these users it makes more sense for the papers to be centered in front of you and for the keyboard to be angled off to the side. Arrange your tools and equipment so that those items used most frequently are placed for easy access.
16. Finally, conventional wisdom holds that there is such a thing as a “correct” posture. In reality, posture change seems to be as important as posture correctness, especially with regard to the intervertebral discs in the spine. These discs lose fluid over the course of the day because of the weight they carry. It appears that posture change is essential to help pump fluid back into the discs. People who stand all day tend to have back problems — but so do people who sit still all day.
This short paper has described a number of ways in which conventional ergonomic practice and wisdom are contradicted by recent research. It is possible that future research will show that some of today’s “progressive” practices are incorrect. In addition, “progressive” ergonomics will invariably be incorrect for some individuals. The ultimate standard is individual comfort (especially over time), tempered by individual preference, control, and choices.
back to top
Organizational Effectiveness If you want to save the office world from musculoskeletal disorders and discomfort, you have to know a lot more than ergonomics.
You have to know how to get things done. To be blunt about it, if you can’t answer the following thirteen questions, you may never manage to help anybody. These are questions that a lot of us wish we’d answered early in the game. They look easy to answer, but take this challenge: write down the answers. In detail.
You’ll get stuck more often than you think.
These questions are an excellent exercise for ergonomics committees. Divide ’em up, do the research (don’t just assume you know the answers), and discuss.
1. Who are the players?
Who currently pays attention to ergonomics? Since you’re visiting this website, you probably are one of those people. Who else? Supervisors? The people who “do the work”? Facilities people?
The people or groups you identify here are potential ergonomics committee members and collaborators.
2. Who currently implements ergonomics?
This may be the facilities or design departments, an ergonomics committee, training departments, individual department managers, or others. Sometimes, only the affected people (and perhaps their private-side insurers) make ergonomic changes.
The people or groups identified by this question should be in the audiences of presentations and training sessions.
3. Who has historically implemented things that result in bad ergonomics? Who has obstructed ergonomics?
These people are among those you should wish to influence. They may be facilities people or people who “design” jobs, or someone else.
4. Who has to notice when there are ergonomic problems?
Usually, medical and human resources people know about more serious cases. Supervisors and/or peers may be the ones who notice both “official cases” and cases of discomfort or complaint. And, of course, the people who are experiencing problems notice … or do they?
These people may be able to assist you in estimating the extent and kind of ergonomic problems at your site.
5. Who has to pay for ergonomic health problems?
Most likely, this is anyone having to do with occupational health payments (medical expenditures, insurance premiums, and disability payments, for example, plus payments for any staff who do administration or treatment).
Ironically, the people identified by this question often have little to do with ergonomics itself.
6. Who might get upset about others doing or measuring ergonomic work?
Does anyone feel they “own” ergonomic activity and might want to protect their turf? Does anyone have ergonomics as a responsibility, yet are inactive and therefore sensitive about it?
The people or groups identified in this question need special attention and communication.
7. Who must approve or support ergonomics or ergonomics budgets?
Typically, this is one or more senior management role, usually in conjunction with a group or person doing organizational strategy and other big-picture activities.
These players need plenty of information, especially information about how their support pays off.
8. Why are “the players” doing ergonomics?
This question often has more than one answer. Possibilities are: An OSHA citation in the past; the possibility of being investigated or cited by OSHA or some other regulatory body; high worker’s compensation, insurance, turnover, absenteeism, or disability costs that are perceived as ergonomics-related; production or quality problems (errors, delays, etc) that are perceived as fatigue- or ergonomics-related; the belief that ergonomics affects recruitment and retention of certain employees; the belief that ergonomics influences customer perceptions of the company; the belief that being responsible for ergonomics enhances personal or departmental image or resources; because employee health, comfort, and satisfaction are valued.
The answers are your organizational hot buttons. Be sure you know whether ergonomics affects the things on the answer list. And accept the fact that it may not be possible to persuade people to value anything different.
9. How does communication happen among “the players” regarding ergonomics?
Do people concerned about ergonomics have a way to get regular information to anyone else? Possibilities include human resources reviews at board meetings, ergonomics or safety committee meetings, bulletin board postings, and employee newsletters.
The answers tell you whether you need to add new communication methods to your existing situation.
10. On a larger scale than ergonomics, what’s important to the company and key players?
How much does the company value, in all its decision areas: the bottom line, stockholder opinion, tradition, appearances, acting like an organizational family, employee recruitment or retention, employee performance, employee morale, spiritual values, etc.
On your first pass you may think your organization values them all. Work on understanding the hierarchy.
11. Are there any conflicts about values or recent shifts in values?
These conflicts are often the symptoms of new ways of making decisions conflicting with old ways. Try to keep up with evolution.
12. Are there any current sources of ergonomic-related data?
Consider: who tracks health and health costs? Does anyone measure productivity in any way? Does anyone measure employee attitudes in any way? Are there records of ergonomics training or workstation changes? Are any data collected repeatedly? Are there any sources of comparisons for any of these kinds of data (for example, for others in the same industry, or other clients of the same insurer)?
Quantitative data regarding situations and results are extremely powerful tools, in terms of being effective (choosing to do the best actions) and getting resources (persuading others that you deserve support). If there are existing data sources, you may be able to leverage them rather than start from scratch.
13. How are spending decisions made?
For example, some businesses rely on the experience and wisdom of key people, while others require detailed proposals containing certain kinds of data and analyses.
Learning the local way to influence decisions saves a lot of wasted energy. Don’t expect decision makers to easily adapt to YOUR version of decision support.