Apple Macintosh LC 575 - Manual (Page 15)

Eye fatigue
Eye fatigue can occur whenever the eyes are focused on a nearby
object for a long time. This problem occurs because the eye
muscles must work harder to view an object that’s closer than
about 20 feet (6 meters). Improper lighting can hasten the
development of eye fatigue. Although eye fatigue is annoying,
there’s no evidence that it leads to permanent damage.
Whenever you’re engaged in an activity that involves close-up
work—such as reading a magazine, doing craft work, or using a
computer—be sure to have sufficient glare-free lighting and give
your eyes frequent rest breaks by looking up and focusing on
distant objects. Remember to have your eyes examined regularly.
To prevent discomfort and eye fatigue:
m Arrange your work space so that the furniture is properly
adjusted for you and doesn’t contribute to an awkward
working posture.
m Take frequent short breaks to give your muscles and eyes a
chance to rest.
Arranging your office
Here are some guidelines for adjusting the furniture in your office
to accommodate your physical size and shape.
m An adjustable chair that provides firm, comfortable support is
best. Adjust the height of the chair so your thighs are
horizontal and your feet flat on the floor.
The back of the chair should support your lower back (lumbar
region). Follow the manufacturer’s instructions for adjusting
the backrest to fit your body properly.
m When you use the computer keyboard, your shoulders should
be relaxed. Your upper arm and forearm should form an
approximate right angle, with your wrist and hand in roughly
a straight line.
You may have to raise your chair so your forearms and hands
are at the proper angle to the keyboard. If this makes it
impossible to rest your feet flat on the floor, you can use a
footrest with adjustable height and tilt to make up for any gap
between the floor and your feet. Or you may lower the
desktop to eliminate the need for a footrest. Another option is
to use a desk with a keyboard tray that’s lower than the
regular work surface.
Setting Up 9