Adjusting Your Chair, Work Surface, And Iris Indigo - Silicon Graphics IRIS Indigo Owner's Manual

Chapter 7: Safety, Maintenance, and Regulatory Information
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tension from sitting in a fixed position. Some chairs can also be adjusted for seat tilt
and depth, armrest height, backrest angle, and lower back support. Check the
instructions that came with your chair to take advantage of its adjustability features.
2. Select a work surface that provides enough space to do your work without excessive
turning, twisting, or stretching. The height of the work space should be adjustable
and, if possible, you should be able to use the mouse and keyboard at the same
height. This helps your neck, shoulders, and upper arms stay relaxed while you
work.
3. Indirect lighting should be used, whenever possible, to prevent glare on the display
screen. If you prefer lower levels of lighting (for example, 200-250 lx) than is usually
found in offices, separate task lighting may be needed for reading documents.
Wearing darker-colored clothing helps minimize glare reflections on the screen.

Adjusting Your Chair, Work Surface, and IRIS Indigo

1. Adjust your chair first, from a seated position if possible. Your lower leg and thigh
should form approximately a 90-degree angle at the knee, and your feet should rest
flat on the floor. If you are short, you may want to use a footrest for better comfort.
2. Once your chair is adjusted, raise or lower your work surface to a height that allows
you to keep your wrists flat and straight while using the keyboard and mouse. The
angle between your lower and upper arm should be 70-90 degrees at the elbow. If
necessary, use a padded wrist rest under the keyboard to support your wrists.
3. To minimize screen glare, position your monitor screen perpendicular to overhead
lighting sources and windows. Do not set the monitor in front of or behind a
window, or parallel to other sources of light. Tilting the screen forward slightly
helps avoid glare. Adjusting the monitor controls to minimize brightness and
maximize contrast may also reduce the effects of glare.
4. Adjust your monitor height so your line of sight in your regular seated position is at
or near the top the screen. You should be able to see the whole screen without tilting
your head forward or backward, within a 60 degree viewing angle of the normal
line of sight. With smaller monitors, this may require using a display stand under
the monitor base. With larger monitors, it may require a longer viewing distance
(see Table 7-1).
5. These adjustment steps should be done each time a different person uses the
workstation.