Working Comfortably
The human body is fragile, more so as one grows older. Those of you above the age of 30 will have realised this. Those below that age will come to realise it soon-you just don’t seem to be as flexible as you were when younger; and niggling aches and pains creep in.
The problem is compounded when you introduce the work factor. Today, many Indians spend more time working than doing anything else, and this is where ergonomics comes in-at least, it should.
Work Forces
It’s still a popular misconception among many that only those who do manual work need to consider ergonomics. This just isn’t true-a worker who daily loads heavy packages on or off a truck is exposed to the same level of risk to his or her back as is a call centre employee. And chances are, the manual worker and the call centre employee will suffer from back pain as the years go by!
The same applies to a teacher who spends hours a day grading papers, as well as the students who spend hours writing them. When it comes to ergonomics, there’s no difference between a journalist writing articles for hours on end on a computer, and a gamer mesmerised by the latest title for hours or days!
The problem lies in a condition called repetitive stress injury (RSI), where you can injure your body by doing the same thing in the same posture day in and day out. RSI can attack anyone, from the manual worker to the gamer.
In what follows, we stick to the dangers posed to us by long hours spent on the computer. To find out how to protect your body while doing absolutely any type of job, refer to the box: The Ergonomic Web on page 78.
The Aches
People have been known to suffer from backaches, neck pain, eye strain, finger and forearm pain after exceptionally long computer use. Of these, eye strain and finger and forearm pain are direct effects of using a computer (of course, it’s the monitor, keyboard and mouse that are to blame). Backaches and neck pains are a result of the way we sit. Let’s take a look at these side-effects one by one and figure out the best practice in each case.
The Back And Neck
Those of you who have suffered severe back pain or slipped discs will surely vouch for the importance of looking after your spine. This is not just another ache, and not just another part of your body: injuries to the spine can be debilitating, and even life-threatening in extreme cases. The body just cannot function without the support of the spine, so you need to make sure you take every little backache and muscle spasm in the spine region very seriously.
At work, the spine is put to risk by the type of chair you use, and how you use it. A chair that hasn’t been designed with ergonomics in mind can cause back pain. But even if you have a good chair designed to take weight off your back, are you sitting the correct way? We’ll soon talk about chairs with good ergonomic design.
The Eyes
Eye strain is almost always associated with the type of monitor you use, the distance and angle at which it is placed, the screen resolution you work at, and also whether you remember to blink and take focus away from the monitor from time to time. More on this later when we look at monitors.
The Fingers And Arms
Very often, discomfort in these areas is not caused by using the keyboard and mouse the wrong way, but simply by not positioning them properly. A chair can also help the arms by providing good padded arm rests, as can placing the mouse at the correct location and height.
The most common complaint is the Carpal Tunnel Syndrome (CTS), a disorder that affects a nerve in the wrists, causing tingling, pain and weakness in parts of the hand. CTS is perhaps the most well-known RSI, and is beginning to affect more people worldwide-all because of the bad placement of a mouse or keyboard!
Office Furniture
Here we show you how you can decide whether the furniture you’re using is ergonomically right or wrong. Remember, just having the right furniture does not mean you’re safe-you also need to know how to use it.
The major cause of back and neck aches, a bad chair can really mess up your spine, especially if you are sitting in it eight hours a day.
As a rule of thumb, a good chair is one in which you feel comfortable. This may sound vague, but our point is that comfort is a very subjective matter-one person’s comfort could be another’s pain. So to begin with, just make sure your chair feels comfortable.
Most chairs today have adjustable parts, so if your chair just doesn’t seem right, try adjusting the height. The proper height is achieved when you can sit in the chair and comfortably rest the soles of your feet on the ground. A low height would be if you find that the backs of your thighs are raised above the chair seat, and too high would be when you cannot comfortably place your feet flat on the ground.
The next thing to look for is an adjustable seat. Since our heights differ, a shorter person would need less seat space, and may need to move the seat backwards towards the backrest. On the other hand, a tall person would need to move the seat forwards.
An adjustable backrest is also important-not just in terms of height, but also in terms of the angle at which it meets your back. The more adjustable the backrest, the more the chances of you feeling comfortable in various positions.
Leaning back on an adjustable backrest helps to take weight off your lower spine, and that’s very relaxing. Contrary to popular belief, a straight-back chair is not exactly ergonomic-not unless you’re strapped to it. It’s better to have a chair with an adjustable backrest that allows you to bend your back a little from time to time, in order to shift the weight.
Apart from the design of the chair, you need to remember to keep shifting your weight about at regular intervals. This helps improve the blood flow to your back and buttocks, and ensures that you do not suffer from RSI. You should try not to slouch in your chair, and take short breaks by standing up and walking about to help the blood circulate. Stretching, more so, after a long stint of sitting, is a beneficial practice.
Monitor Placement And Lighting
Lighting? Yes, even lighting is a factor when deciding monitor placement. You’ll often see someone at your workplace twisting and contorting when trying to read a particular area of their monitor. So also, you may place your monitor in an equally awkward position, just to be able to view it properly.
When deciding where to place a monitor, it’s best to make sure there’s no light source behind the user, as this causes a glare on the screen and makes areas of the screen unreadable. Also, in larger offices where the workforce is seated in cubicles, rows and columns, such as in a call centre, diffused lighting is a good idea. This cuts out the one bright source of light and reduces the glare on the monitors.
The second most important aspect is the distance of the screen from the eyes. The closer the screen, the more the strain on the eyes. This is easily demonstrated by doing a simple test: hold up your index finger at a full arm’s length from your face. Now focus on your nail and gradually bring your finger closer to your eyes. You’ll notice that the closer the finger gets to your eyes, the more strain you’ll feel while focussing.
So what is the correct distance at which your monitor should be placed? The answer is more complicated and involves more than a simple measurement in inches. Though it is widely suggested that you place the monitor at least two feet away from the eyes, this doesn’t account for the other variables you come across when dealing with computer monitors.
For instance, placing a 14-inch monitor two feet away from your eyes is good, but what about those with 19 or 21-inch monitors? Then there’s the problem of resolutions. Placing a 19-inch monitor three feet away from the eyes might seem like a good idea, but when you’re running at a resolution of 1600 x 1280, this could make the text on the screen look minuscule, and force you to strain your eyes anyway!
A good practice is to keep the monitor at least 25 inches away from the eyes, and adjust to the resolution that causes the least eye strain. Instead of using a 19-inch monitor running at a resolution of 1600 x 1280, placed at 25 inches away from the eyes, consider placing the monitor three feet away, and running it at a resolution of 1280 x 1024 or 1024 x 768.
The next consideration is the monitor tilt, and the height at which it is placed. Here’s where your table comes into play. Since you’ve already decided on the height of your chair, you need to make sure the tables are low enough to keep the monitor at the correct height. Remember, it’s a lot easier to increase the height of a monitor by placing something under it than it is to decrease the height.
Since heights are very subjective, monitor placement is always decided by angles. Studies have found that in order to protect the neck, a monitor’s viewing area should be 15 to 50 degrees below horizontal eye level. This means that if you sit in your chair and look straight ahead, focusing on an object at the same height above the ground as your eyes, the top of your monitor should be at a minimum of 15 degrees below your line of sight, while the bottom of the monitor screen should be a maximum of 50 degrees below the line of sight. This is illustrated in the diagram alongside (see Monitor Placement).
A few other things to consider are the results of studies that have shown that white text on black backgrounds seem to strain the eyes more than black text on white backgrounds. So as a rule of thumb, try and work with dark text on light backgrounds. Keep in mind that correct ergonomic placement of the monitor requires the monitor to be tilted away from the eyes, so that the bottom of the screen is closer to the body than the top of the screen.
To better understand why a tilt is needed, notice the way you’re holding this copy of Digit. You’ll see that the magazine is tilted away from you, just as when you hold anything else, say, a newspaper or book. This happens because we’re used to objects being further away when at the eye level and closer when below our line of sight.
If you sit down and look straight ahead, you will notice that the objects at and above your line of sight are further away, and the objects in your field of vision that are below this line of sight are much closer. It’s only obvious that if you tilt your monitor away from yourself to reflect a more real-world sight, you will strain your eyes less.
The next step towards protecting your body when working with computers is to protect your hands-your fingers, wrist, forearms and elbows. As we mentioned earlier, the most common injury resulting from computer use is the Carpal Tunnel Syndrome, caused by excessive use of a keyboard. Though a keyboard that solves this problem has not yet been invented, especially for those who have to type hundreds of thousands of words a day (data-entry operators and the like), there are models that try and reduce the risks.
Split keyboards: These are keyboards that are broken into two parts. Some designs feature a single keyboard with the keypad split in two-and each half is positioned at a different angle. This style of keyboard tries to solve the problem of unnatural angles for the wrists.
To illustrate the problem, look at your regular keyboard. It is flat and has the same angle towards your body for all keys. Now place your hands over the keyboard as you would when beginning to type. You’ll notice that your wrists are bent slightly outwards (towards your little fingers). This posture is not natural, and we often find ourselves rotating our keyboards in one direction or the other to ease the stress on our wrists. This typing posture is in sharp contrast to the way we place our hands on, say, the dinner table. You’ll notice that at the dinner table, your hands are placed much further apart than when at the keyboard. This is the specific problem that split keyboards attempt to solve.
Palm rests: Most keyboards today come with palm rests. The simple reason for a palm rest is that it allows your hands to be placed on a firm surface rather than being held in the air by your muscles. This reduces the strain on your muscles and helps relax your arms a lot more.
Tented keyboards: These keyboards look very funny at first, until you understand why they’re made that way. Another simple experiment: stand up and leave your arms loosely by your side. Now bend your arms at the elbow and bring your hands up, perpendicular to your body. You’ll notice your palms are facing each other (inwards), and not the floor. This is in sharp contrast to the way they are placed when using a normal keyboard, where your palms are resting on the table or palm rest, and facing the floor.
Even in the previous dinner table example, if you notice that when you put your hands up on a table, comfortably, the palms are never facing the table: they face each other. This is the natural position for your hands. So although split keyboards solve the problem of angles, they don’t solve the problem of natural palm placement.
This is where tented keyboards try and kill two birds with one stone-the keyboard is split, and also angled like a tent, to keep your hands in as natural a position as possible when typing. Of course you will make a good many typos trying to get used to this style of keyboard, and you’ll also slow down your typing speed, but as with everything else, you’ll get used to it.
Tented keyboards are an option only for touch typists, for those of us who look and type, the split keyboard is as good as it gets!
Negative-slope keyboards: These are keyboards that have height-raising feet at the front, instead of at the back like most keyboards. Here’s another simple test. Hold your hands out in front of you, palms facing the floor and fingers straight. Now bend the hand downwards from the wrist so that your fingers point at the floor. Now do the same thing in reverse and try and point your fingers at the ceiling. You’ll see that it’s much easier to bend the hand downwards than upwards. What negative slope keyboards do is try and ensure that your wrists bend upwards as little as possible, and even favour a bend downwards.
It’s widely acknowledged that placing a keyboard low is desirable so the arms can straighten as much as possible. Unfortunately, a standard keyboard placed low will cause you to further bend your wrists upwards, thus risking harm. So if you like to place your keyboard as low as possible, a negative-slope keyboard could help ease the tension in your aching wrists.
Ergonomic mice: Though many manufacturers make ergonomic mice, all of which are designed differently and can be really expensive, it’s perhaps only gamers and those who use the mouse for extended periods of time without breaks, who might need them. The designs of ergonomic mice are decided in pretty much the same way as that of the aforementioned keyboards.
In Short
From what you’ve read thus far, it should be obvious that good ergonomic design means keeping your body in as natural a position as possible, reducing strain on the muscles and tendons. This is why ergonomics is often called the science of fitting a job to the person, rather than fitting a person to the job.
No matter how stressful your work or how busy your schedule, always remember to take a break, shift the body, stretch and relax-all this will help make you more productive, and also eliminate the unwanted costs of balms and sprays! If nothing else, by following these guidelines, you might just start to feel a little younger!
The Ergonomic Web |
There are plenty of online resources that will give you all the information you need about ergonomics, and more. Most of these Web sites are dedicated to the science of ergonomics, and you can be sure that the information provided is correct. Here’s a list of a few sites you should visit:
The Ergonomics Society (www.ergonomics.org.uk) This is a society of people dedicated to the study of ergonomics. You can find everything from information to job vacancies for ergonomic specialists here. Office Ergonomics (www.office-ergo.com)
This is a site that’s dedicated to providing you information on how you can be more ergonomic at work, from tips for employees to guidelines for employers. Ergonomics: Posture Movement and Ergonomics(www.ergonomics.org) Cornell University Ergonomics Web (http://ergo.human.cornell.edu/)
This site has information from research studies and class work by students and faculty from the Cornell Human Factors and Ergonomics Research Group. International Ergonomics Association (www.iea.cc) |