In search of the perfect chair - selecting a chair for a home-based business

Home Office Computing, August, 1991 by Christopher Murray

A home office needs more than computers, printers, and modems. Furniture, especially chairs, can be one of the most important purchases we make. A chair can radically affect productivity and enjoyment of work. And a chair can have a profound effect on health, since chronic backache is such a widespread problem for desk-bound computer users.

A good chair is an investment in your back that will pay dividends for the rest of your life. So sit up and take notice. The following questions and answers will guide you in your quest to keep your weary bones comfortable and rested. After reading, sit back, relax, and turn to the chart for a sampling of models from the leading commercial office-chair manufacturers.

What should I look for in a good office

chair?

Adjustability. A good chair is one you can fine-tune to fit you. The best ones adjust automatically based on the user's weight distribution, or manually, with easy-to-reach knobs or levers. The more adjustments possible, the more expensive the chair.

The most important adjustment is the height of the chair's seat. There are two basic ways to raise and lower a seat: the screw post and the more expensive gas lift mechanism. The old piano stool used a screw post: spinning the seat raised or lowered the seat height. A gas lift mechanism is a cylinder filled with air, and it works much like the shock absorbers on a car.

Both methods work fine. However, you can operate the gas lift in seconds with a gentle tug on a lever while sitting in the seat. The screw post requires you to climb under the chair and rotate a ring or a large nut on top of the chair's base. While this is somewhat inconvenient, you probably won't have to change the setting much if you are the chair's only user.

On the other hand, some people like to be able to make small adjustments in seat height throughout the day, while moving from handwriting, say, to keyboard entry. Under these conditions, a gas lift becomes more important. A subtle but alluring feature is that a gas lift acts as a shock absorber or spring. Flopping into the chair from two feet up is no problem.

What other kinds of adjustments are important?

The second most important adjustment is the back-tilt mechanism. As you sit, your heels should rest comfortably on the floor, to maintain circulation in your legs and feet as you lean back. When a chair is improperly adjusted, we tend to compensate in all sorts of ways: We put our feet up on the desk, rest them on the edge of an open file drawer, cross our legs, and so on, all to reduce pressure behind the knee.

The mechanisms that keep our heels on the floor are called posture-back or knee-tilt mechanisms. With a knee-tilt mechanism, as you lean back, the rear of the seat drops down without raising the front edge. Posture-back chairs have a back which moves independently from the seat. Both mechanisms accomplish the same thing, which is to keep the lower back at the proper angle with respect to the legs and feet.

Is it important that a chair have casters?

Casters make rolling from keyboard to fax machine to printer a simple matter. However, many people use four-legged or sled-based chairs, preferring them for functional (or financial) reasons. There is nothing inherently wrong with a stationary chair of this type, as long as you find it comfortable enough after a long day of sitting.

Caster-based chairs have a smaller footprint than stationary ones, and a five-pronged caster base is smaller than a four-pronged base, factors you'll need to consider if space is tight. Floor surface is a major concern as well. The typical residential carpet will swamp any chair, casters or not. If you can't replace the carpet with a short-nap industrial one, you have two choices. The first is to find a chair with three-inch casters instead of the standard two-inch ones. The larger wheels "float" somewhat better. The other solution is to buy a chair pad, which is simply a sheet of stiff plastic that provides a hard surface for wheels to roll on. Unfortunately, the standard pad is generally too small for most offices. And rolling off the pad is right up there with paper cuts in my book of office irritants.

Are kneeling-type chairs practical?

In the early eighties, a new chair appeared on the scene: a forward-tilting seat. The theory is that if you sit with your thighs sloping downwards from the pelvis, the opened angle between your back and legs tips your pelvis forward and thus maintains the natural curvature (or lordosis) of the lower back. This posture is most dramatic in the Balans chair, a backless "perch" (with an 11-degree angle built into the seat) on which your weight is partially supported by a kneeler in front of the seat. The Balans chair is surprisingly comfortable, but many people find it to be useful mainly as a task-intensive chair, for keyboard entry or similar focused work. As a general-purpose office chair, however, it lacks something (namely, a back).