Silicon Graphics CHALLENGE L, User Manual, Page: 111 / 164

Tips for Setting Up and Using Your Workstation
95
Adjusting Your Chair, Work Surface, and Monitor
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 increased comfort.
2. Once your chair is adjusted, raise or lower your work surface to a
height that allows you to keep the 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 with
its screen or its back facing a window, or parallel to other sources of
light. Tilting the top of 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 that your line of sight in your regular
seated position is at or near the top of 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 6-2).
These adjustment steps should be followed each time a different person uses
the monitor.
System Usage
1. When using the keyboard, mouse, or other input devices, keep your
wrists flat as much as possible, and do not rotate your hands inward
toward the thumbs or outward.
2. Electronic keyboards and input devices do not require as much force to
operate as manual typewriters. Type lightly on the keyboard and click
the mouse gently.