From http://lowendmac.com/bookrev/br07/0713.html

General Workstation Tips:

Screen monitor should be at eyelevel

Elbows rest at the side, bent at a 90 degree angle

Wrists are straight (neutral) and rest on a gel pad

Knees are level with or slightly lower than hips

Seat edge (by knees) is soft

Feet rest on the floor or on a footrest

Low and middle back is supported

Chair and desk height are appropriate for your height

 

 

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