The first ergonomic consideration for the keyboard and mouse is height. Your chair and seated position should be relative to the height of the desk and your position to the work surface and keyboard. In general terms this means the keyboard and mouse should be just below your elbow height when your forearms are parallel to the floor.
Work surface should have at least 100mmn – 150mm free space in front of any input device, this space can be used to support the hand or wrist.
Work surface edge should be shaped to avoid cutting into the wrist.
When seated in a comfortable position relative to the desk, your arms should rest at your sides, forming a 90 degree angle at each elbow. The keyboard should rest on the desk, set in a negative tilt position, which means that the front of the keyboard (space bar edge) is lower than the back (although some now recommend that the keyboard be flat). To ensure that the keyboard is fully centralised, the letter ‘B’ should be in line with your bellybutton.
Always ensure that your wrists are in the neutral position, which means the hands and wrists are in line with your forearms. Be gentle, use a soft keying action – do not ‘hammer’ the keyboard.
Learn to use shortcuts on the keyboard rather than always using the mouse. Most shortcut key combinations are displayed alongside the relevant item in the pull down menu of the application.
Don’t lean your wrists or forearms on the desk when using the keyboard this puts a direct pressure on the wrists. If you rest your wrists whilst inputting get a wrist support or drop the level of the keyboard.
When handling a mouse, keep your hand and wrist in line with the forearm. Avoid bending the palm at the wrist; either to the right or left or up and down.
Avoid mouse shapes that may cause the fingers or wrists to be bent sideways or upwards when grasping the mouse.
If you choose to use a wrist rest, using one with a broad, flat, firm surface design works best, and rest the heel of your palm on this NOT your wrist. Try not to rest your hands on the support while you’re actually typing, but rest them in between bursts of typing movements. Avoid soft and squishy wrist rests because these will contour to your wrist; restrict the freedom of movement of your hands.
Wrist supports should only be used in between periods of keying or mouse work. Your hands and wrists should hover over the keys. Otherwise the use of a rest will compress the carpal tunnel and inflame the median nerve…
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