• Female: 24.5 to 27 inches in height.
  
  
• Male: 26 to 29 inches in height.
  
  
• Leg room: A space of 27 inches wide x 27 inches in height x a minimum of 15 inches in depth is recommended.
  
  
• Knee clearance of 2 to 4 inches.
  
  
• If seated in a cubicle, keyboard / keyboard tray should be placed in the corner, use a keyboard tray corner brace.
  
  
• If using a laptop computer, due to the poor ergonomic configuration of laptop computers, a laptop holder is recommended in order to optimize positioning of the screen and an external keyboard are recommended. Please refer to our " Laptop Ergonomics" for more details on optimizing your laptop set-up with " Laptop Accessories".
  
  
• Keyboard and keyboard tray should be placed directly in front of the user.
  
  
• The keyboard/ keyboard tray should be adjustable in height and range from 24 to 26 inches from the floor; this should be set at approximately elbow height for the computer user. An ergonomic adjustable keyboard tray is considered essential in order to provide this required flexibility for proper joint positioning.
  
  
• If seated in a cubicle, a keyboard tray corner brace should be used in order to maintain proper seated position with the keyboard tray at the corner.
  
  
• The position of the computer keyboard/ keyboard tray should allow the shoulders to be at 10 to 30 degrees of flexion and relaxed and the user's elbows to be at approximately 90 to 100 degrees.
  
  
• The position of the keyboard/ keyboard tray should allow the wrists to be in a neutral / straight position. A positive tilt of the keyboard is not recommended. (A positive tilt is when the keyboard tray is set up higher on the back of the keyboard in relation to the front.) This position tends to promote excessive wrist extension postures and cause computer-related wrist/hand pain. A negative tilt may be recommended to keep wrists in a neutral position. This can only be accomplished with the use of an adjustable keyboard tray. (A negative tilt is when the keyboard tray is set down lower on the back of the keyboard in relation to the front.).
  
  
• If using a laptop computer, a laptop holder is recommended in order to optimize positioning of the screen and an external keyboard such as the Ergo-Q compact keyboard are recommended. Please refer to our " Laptop Ergonomics" for more details on optimizing your laptop set-up with " Laptop Accessories".
  
  
• Wrist rests are commonly seen in the office setting and may be recommended in order to allow the operator rest to alleviate computer-related pain and stress on the shoulders, arms and hands. Make sure the computer user is not leaning or putting pressure on the wrist rests while performing the typing activities. This in effect results in another computer-related ergonomic risk factor: contact pressure, which may inhibit blood flow through the carpal tunnel, possibly leading to a computer-related cumulative trauma disorder or carpal tunnel syndrome.
  
  
• The computer mouse should be placed on the same level as the keyboard tray, to minimize excessive shoulder flexion and elbow extension, which may result in increased pain and fatigue. This is why using a keyboard tray with a computer mouse platform is so critical. All of our keyboard trays have this mouse platform adjacent to the keyboard.
  When using the computer mouse, arms should be at the computer user’s side, relaxed and the elbows should be flexed 90 to 100 degrees.
  
  
• Alternative input devices, such the Contour RollerMouse Classic or RollerMouse PRO are recommended in cases of continuous or excessive computer and computer mouse usage and/or if the computer user already has computer-related pain.
  Please read more about " Ergonomic Computer Mouse Designs", " Computer Mouse Features" and " How To Choose an Ergonomic Computer Mouse".

Click link for full article and resources on" Ergonomic Guidelines for Keyboard /Keyboard Trays" 

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