Proper selection and arrangement of the computer keyboard helps reduce exposure to awkward postures, repetition, and contact stress. The keyboard should sit directly in front of the users. Shoulders should be relaxed and elbows close to the body. Wrists should be straight and in line with the forearms.
Keyboards, pointing devices (mouse), or working surfaces that are too high or too low can lead to awkward wrist, arm, and shoulder postures. For example, when keyboards are too low you may type with your wrists bent up, and when keyboards are too high, you may need to raise your shoulders to elevate your arms. Performing keying tasks in awkward postures such as these can result in hand, wrist, and shoulder discomfort.
Adjust the chair height and work surface height to maintain a neutral body posture. Elbows should be about the same height as the keyboard and hang comfortably to the side of the body. Shoulders should be relaxed, and wrists should not bend up or down or to either side during keyboard use.
Remove central pencil drawers from traditional desks if you can't raise your chair high enough because of contact between the drawer and the top of the thighs.
A keyboard tray may be needed if the work surface or chair cannot be properly adjusted. The keyboard tray should reduce awkward wrist angles by lowering or raising the keyboard or chair to achieve a neutral wrist posture.
Adjust the keyboard tray tilt to achieve a neutral wrist posture.
A keyboard or pointer/mouse that is too close or too far away may cause you to assume awkward postures. If the keyboard is too far, away employees will have to reach with the arms and lean forward with the torso. If the keyboard is too close to the users, the elbows will be at extreme angles. These awkward postures may lead to musculoskeletal disorders of the elbows, shoulders, hands, and wrists.
The pointer/mouse should be positioned next to the keyboard. Improper placement of the mouse can lead to awkward postures, contact stress, or forceful hand exertions while using the device.
Position the pointer/mouse to allow you to maintain a straight, neutral wrist posture. This may involve adjustments in your chair, desk, keyboard tray, etc.
If the keyboard tray/surface is not large enough to accommodate both the keyboard and mouse, try one of the following to limit reaching:
Use a mouse platform positioned over the keyboard. This design allows the mouse to be used above the 10-key pad.
Install a mouse tray next to the keyboard tray.
Use a keyboard without a ten-key pad, which leaves more room for the pointer/mouse.
Install keyboard trays that are large enough to hold both the keyboard and mouse.
Use a mouse pad with a wrist/palm rest to promote neutral wrist posture.
Substitute keystrokes for mousing tasks, such as Ctrl+S to save, and Ctrl+P to print.
