Comfortable Computing

Working in comfort is not the luxury that it may seem. Aside from health and safety issues, productivity is at stake.

Few employees spend as much time in apparent ergonomic torment as professional cyclists. With some of the most sensitive parts of the body perched on a narrow, hard saddle, the back is poised almost horizontal, and the neck extended to allow forward vision and facial impact with bees.

Opportunities for comfort stops are very infrequent, and they even have to eat and drink on the move. Their working environment could be baking heat, or blinding blizzard. By comparison, setting up your working area in the shelter of an office or home should be a doddle.

Position and posture

As far as position goes, the basic aim is to place each part of the body in its ‘neutral’ position, minimising ‘unnatural’ stress on joints. For most people, this entails sitting with:

  • feet resting on the ground with lower legs roughly vertical to the knees,
  • thighs in a near-horizontal plane,
  • back inclined backwards slightly with support for its natural curves, particularly in the lower lumbar region,
  • upper arms in vertical line with the body,
  • forearms near-horizontal with the wrists supported and straight in front of the body at about shoulder width,
  • head and eyes looking straight ahead at a screen which is in a vertical plane, perpendicular to the gaze.
The conventional approach to workstation design. Yamavu via Wikimedia Commons.
The conventional approach to workstation design. Yamavu via Wikimedia Commons.

This is illustrated in countless books and websites such as Posturite‘s and Wikipedia.

With the clean aesthetics of da Vincian anatomical geometry, it is an ideal posture that few of us assume, and hardly any computer user maintains for more than a small fraction of their working time. In reality we turn to talk on the phone, slouch in thought, fidget and move repeatedly, and more detailed guides such as that at Cornell University’s Ergonomics Web contain more pragmatic advice.

If you are the only person who ever uses your Mac and workstation, then you may be able to set it up to perfection using fixed furniture. But for most, and all situations where two or more users share, some degree of adjustment is necessary.

The most flexible solution is the combination of a chair with adjustable height and position and an adjustable display. Merely providing adjustable items does not of course ensure that they are correctly adjusted. It is important to get a wise colleague to check your set-up, both when you are posed for the purpose and later while you are engrossed in your work.

Light and heat

When your display is optimally positioned relative to your eye, it may still be a visual disaster if the area is badly lit. Suffuse lighting which avoids glare is ideal; interesting though a view through a window might be, if that admits bright sunlight from behind the display most users will be forced to squint, becoming fatigued and suffering headaches. The vogue for attaching filters and hoods to displays has passed, as people have realised that window blinds and room layout are much more effective at controlling glare and dazzle.

Soft winter sunlight can bring cheer when the days are short, but the chances are that summertime insolation will make your workstation unbearably hot too. Effective air conditioning remains relatively unusual in the UK, but an even and comfortable thermal environment is well worth the effort and cost. Bodged conditioning can result in excessive thermal gradients, with the feet freezing whilst your face is hot enough to sweat; steady air movement without drafts is also important.

By the time that you have installed all the gear from footrest up to adjustable lighting, and littered the walls with air conditioning units, the office may look a real mess, and pose its own trip and other hazards. Ironically many designers and engineers pay least attention to their own working environments, when a little time and effort are amply repaid by results.

Less usual issues

Unusual devices such as graphics tablets and touchscreens pose unusual problems; conventional thinking and sources of wisdom may be less helpful, and you must be careful not to just chuck them in as extras.

A touchscreen is a good example of a multifunction device which makes conflicting demands on different parts of the body, requiring comfortable finger access but positioning relative to the eye as any other visual display. Currently there is no obvious solution to this unless it can be moved around as you would an iPad, according to which function is the dominant factor at any given time.

Beware of ‘neat’ ideas that present unsurmountable ergonomic conflicts.

Poor outcomes and problems

Legal claims handlers and occupational health advisors can list the many ailments that result from poor working environments. Headaches can result from uncorrected vision, screen glare, and neck strain generated by misalignment of the eye and display. There is a useful rule of thumb that morning headaches should take you straight to your GP, whilst those developing during working time are more likely to result from poor posture, vision, or of course non-physical work stress.

Bad seated posture is a common cause of back, neck, and leg pain. Koivuma via Wikimedia Commons.
Bad seated posture is a common cause of back, neck, and leg pain. Koivuma via Wikimedia Commons.

Backache is probably the most common chronic complaint among Western adults. Good working posture goes a long way to prevent it, but it is also vital to change that posture during regular breaks in which you can stretch and walk around. Apps such as Stretch can serve as a reminder. These days smokers have a distinct advantage in having to step outdoors for breaks, leaving healthier colleagues to slog on in mounting discomfort.

Danger signs that should take you rapidly to your GP are pains which radiate into the arms or legs, or any loss of sensation or weakness in the arms or legs. Keeping fit and remaining slim are a great help, as excess body weight increases the loads on the back and leg joints. Those who are very tall may need special chairs and other equipment to accommodate them in comfort, particularly as many are already prone to back problems.

Repetitive strain injury (RSI) has cost some employers prodigious damages when sufferers have been successful in pursuing claims. It appears to be a complex over-use injury arising from repeated movements typically of the fingers performed with wrists and forearms stressed and unsupported.

It is most common in those operating older keyboards which required considerable force and/or key travel, especially those with higher typing speeds. Thankfully it has become rarer as a result of efforts to maintain correct posture, provide wrist support, and ensure sufficient breaks.

There are some who have suffered severe RSI in the past and are still unable to use conventional computer input devices such as a keyboard and mouse. They normally cope better with speech-recognition software, but a small minority continue to suffer severe long-term disability: a tragic reminder of the serious consequences of ignoring the need for good workstation design.

If you think that you are developing a health problem from your work, you should of course first visit your GP. Physiotherapists can be very helpful in treating musculo-skeletal problems, and ergonomists are the real experts in prevention.

Workstation design is a key part of office health and safety, but long before you should encounter those issues, you should be concerned with encouraging error-free productivity. Anyone trying to work with strain and pain will perform their work more poorly as a result.

Are you sitting comfortably?

Selecting the perfect chair for your workstation is one of your most important tasks, as it plays the prime role in positioning your legs, back, neck, and arms. Unfortunately we are often easily swayed by appearance, designer label, materials, novelty features, stacking and storage, or constrained by cost.

Many visually stunning designs turn out to be ergonomic failures, in which their designers would hate to be confined. If you really want to spend your working hours in an Eames moulded plywood chair, or more comfortable lounge chair, you could be suffering in style.

An ErgoChair by Tergon. Tergon via Wikimedia Commons.
An ErgoChair by Tergon. Tergon via Wikimedia Commons.

Most users find classic omni-adjustable office chairs, with full-height back, armrests, and rotating seat, the best general solution. When you know how to set them up to achieve the ideal working position, they are good, but their controls are not always easy to use, and many never take the time and trouble to get the best out of their chair.

Unconventional solutions that may have particular appeal to those who suffer back pain include ‘kneeling chairs’, now sufficiently popular as to be offered by national chain stores, and ‘ball chairs’.

Kneeling chairs have a good track record of letting you put your back into its natural curves and easing discomfort. Expensive models are of adjustable height and as adaptable and sophisticated as high-end office chairs, but cheaper models usually require lower desk surfaces, which can be hard to accommodate.

Some users find unconventional seating far better, but some do not. Koivuma via Wikimedia Commons.
Some users find unconventional seating far better, but some do not. Koivuma via Wikimedia Commons.

Recent ideas to support near-standing positions with a ‘stand up chair’ have weaker evidence and should be treated with healthy scepticism; those who would otherwise have to stand up for long periods, whilst ironing or at a lab bench, may find these unconventional seats beneficial, but the great majority would not welcome replacing a good adjustable chair with what might amount to an expensive bar stool.

Helping Hands

The most fastidious keyboard and mouse users know categorically which models they really like, and it can be hard to persuade them to even try anything different. Although many of them castigate Apple’s current products, the latter are probably far better suited to sustained productive work.

Apple’s Wireless Keyboard is compact, and suitable for both touch-typists and those who hunt and peck more. Lacking a cable, it can be positioned wherever you wish to place your hands, and moved around to accommodate other input devices and different work positions. Key travel is sufficient for positive action, but short enough to reduce the risk of RSI, and for heavy numeric work it can be supplemented by a numeric keypad.

Apple's Adjustable Keyboard: an ergonomic innovation but market failure. via Wikimedia Commons.
Apple’s Adjustable Keyboard: an ergonomic innovation but market failure. via Wikimedia Commons.

Previous attempts to improve on traditional keyboards, such as Apple’s Adjustable Keyboard, looked impressive but most users did not find them comfortable. Others who tried to copy the idea omitted the vital adjustable angle, creating unwieldy monsters. Because key assignments in OS X are determined by the software keyboard layout chosen in the Input menu (Language & Text), those who prefer a Dvorak layout can readily use it, although there is no evidence of its practical superiority.

For years Apple prescribed a simple single-button mouse, but have relented and offered a succession of configurable multi-button designs. Again these are most flexible when wireless, as they can be pushed out of the way if you need to switch to a proper graphics tablet or other device.

The Apple Magic Trackpad and Wireless Keyboard. Courtesy of, and © Apple.
The Apple Magic Trackpad and Wireless Keyboard. Courtesy of, and © Apple.

Greater reduction in the risk of RSI can be achieved by changing from throwing the weight of a mouse around, to the eloquent gestures of a trackpad. Once considered an inferior emulation of a mouse for laptops, configurable gestural controls have proved superior for many. However those who have used a mouse for years need time to switch.

Updated from the original, which was first published in MacUser volume 29 issue 10, 2013.