Height -- The keyboard should be placed at approximately seated elbow height. A worker's fingers should fall on the "home" row of keys while the arms fall straight down from the shoulders and the forearms are held parallel to the floor.

Wrists -- Wrists should be held in a neutral position, in line with the forearm, with no bend up, down, or to either side, while typing. When your arms are dangling straight down from the shoulders and relaxed, the wrists are in their natural position. This position should be duplicated as closely as possible while using the keyboard. Studies show that cumulative trauma disorders associated with computer use can be attributed to repetitive movements made while the wrist is bent up, down or sideways from a neutral position. This causes pressure to be exerted on the tendons, nerves, and blood vessels passing through the carpal tunnel.

Arms -- Arms should rest at your sides, with forearms held at approximately a 90 degree angle from the upper arms. Elbows should be kept as close to the body as possible with the shoulders relaxed to reduce strain on the upper body.

Posture -- The head should be kept over the shoulders to reduce strain on the neck and improve blood flow to the upper body. The back should be upright, against the back of the chair, so the weight of the upper body is supported by the chair. The chair should support the natural inward curve of the spine in the lower back. A pillow or rolled towel can be used to provide extra lumbar support if needed.

Pressure -- Moderate to light pressure should be used when typing. Use of excessive force can play a major role in cumulative trauma disorders. Keyboards should be operable with a light touch.

Keyboard slope -- The surface angle of the keyboard should be adjustable so the keys can be reached easily with the wrists in a neutral position. Some keyboards can be placed flat or angled slightly upwards at the back. A new keyboard is on the market that incorporates a negative slope, down and away from the user, and is also advertised as encouraging a neutral wrist position.

Wrist rests -- Wrist rests should only be used to support the wrists in pauses between typing if this is comfortable for the individual. Placing the wrists on a wrist rest while typing can create a bend in the wrists and pressure on the carpal tunnel. Wrist rests should have rounded, not sharp, edges and should provide a firm but soft cushion.

Back to Ergonomics