Why is finding the right chair so important?
Today, in industrialized countries, many people sit for most of the time that they are awake. They sit while having breakfast, while going to work in cars or buses, in school classrooms, in meetings, in offices, during dinner, and at home while watching television. Many people also sit at work operating machines which new technology has developed to replace manual work. Although sitting requires less physical effort than standing or walking it puts a lot of stress on lumbar area. Combined effects of a sedentary lifestyle and a job that requires sitting can lead to many health problems.
What should I consider when selecting a chair?
A basic rule of ergonomics is that there is no such thing as an "average" person. However, providing a chair specifically designed for each individual is not practical. The only solution is to provide workers with fully adjustable chairs that can accommodate a maximum range of people (typically around 90 percent of the population; workers falling in the ranges of 5% of the shortest and the tallest will need custom-made chairs).
Choose a chair with:
lcontrols that are easy to operate from sitting position
la seat that adjusts for both height and tilt
la seat that does not put pressure the back of thighs or knees
la seat with a front edge that curves towards the floor
lbreathable, non-slippery fabric on the seat
la backrest shaped to support the lower back
la stable five-point base
lwheels or casters suitable for different type of flooring like hardwood, carpet and marble floor
la swivel mechanism
larmrest that can be adjusted to the elbow height when your upper arms are hanging down and your forearms are at about a 90 degree angle to the upper arms
larmrests that do not interfere with free movements within the workstation
How to Adjust the Height of an Office Chair?
There are different styles and designs of computer or office chairs. Most new models are adjusted pneumatically. Pneumatic office chairs have a lever or a button below the seat that you can push or pull to adjust the height. Older computer chair models can be adjusted by turning a thick bolt (these bolts usually have a thick plastic molded cover with finger grips). Adjusting the height of your office chair to fit your body type is very important. Back ache and pinched nerves can occur otherwise -- especially after long periods of sitting.
Adjusting an Office Chair:
1. Place the chair in front of the desk or table where you will be sitting most often. This makes it easier to adjust the chair according to your back support and height needs.
2. Become familiar with the chair's adjustments. Locate the lever or button, if the chair is pneumatic, or bolt, if the chair is not pneumatic, for adjusting the height. These will usually be located directly below the seat. There may be two levers or bolts. One will be for adjusting the back support and the other for adjusting height. Models vary, and you will need to try each to discover which button adjusts the height and which button adjusts the back support.
3. Adjust the height. Stand in front of your chair and press the pneumatic lever (up or down, depending on the chair model) with one hand. Gently lift on the seat of the chair with the other hand. The chair seat should move slowly. Office chairs that are non-pneumatic can be moved by loosening the height-adjustment bolt by hand and pulling up or down on the seat until it is at the right height. Lock the position by re-tightening the bolt.
4. Test the chair's height. Carefully, sit down on the chair when it seems to be at the right height. Your feet should rest flat on the floor, with your knees lower than your waist and bent slightly wider than a right angle. If you need to, repeat step three until you can sit in your office chair in the correct position. Some chairs will automatically lock into place once you release the pneumatic lever. Others may have a separate locking mechanism. Be sure to check this before placing your full weight on the chair.
1. You can adjust the height of most computer chairs while you are sitting in them, but it usually causes less wear on the chair if you adjust it up or down with little or no weight on it.
2. Computer chairs will last longer if they are treated with care, so do not raise and lower them more frequently than necessary.