Ergonomic Hazards. Visual Display Units
4. Work Conditions
As regards the work space:
- The walls are to be pale matt in colour.
- The light bulbs are to be provided with diffusers.
- The general lighting is to have an intensity of 150 - 300 lux.
- Ambient noise for normal work is to be lower than 65 - 70 dB (A) and for work that requires concentration, lower than 55 (A).
- The dry temperature is to be 19º - 24º and the humidity, 40% - 70%.
As regards the workstation itself:
- The optimum visual distance is to be 45 - 55 cm.
- The visual angle is to be 10º - 20º with respect to the horizontal.
- The copyholder is to be at the same height as the screen.
- The keyboard is to be at a height of 60 - 75 cm from the floor and should not be placed on the edge of the desk, leaving 10 - 15 cm for wrist support.
- The seat is to have five legs and an adjustable back. The adjustable seat is to have a height of 38 - 48 cm. The seat is to have a depth of 40 cm. The angle of the arms is to be 90º and that of the legs, more than 90º.
- The foot rest is to be adjustable in height.
As regards the screen:
- Keep it clean.
- Away from windows.
- Perpendicular to lights.
- Devoid of reflections from the workstation.
