| A very common reason for discomfort glare being a problem for computer workers is lighting. Light often leaves the overhead fluorescent fixture in a wide angle, resulting in light directly entering the eyes of the workers. |
Lighting Problems |
Good lighting design can significantly
help reduce discomfort glare. Light
leaving the fixture can be directed so that
it goes straight down and not into the
eyes of the room occupants. This is most
commonly accomplished with the louvers
in the luminaire or fixture. An even better
solution is indirect lighting in which the
light is bounced off the ceiling - resulting
in a large low luminance source of light
for the room.
help reduce discomfort glare. Light
leaving the fixture can be directed so that
it goes straight down and not into the
eyes of the room occupants. This is most
commonly accomplished with the louvers
in the luminaire or fixture. An even better
solution is indirect lighting in which the
light is bounced off the ceiling - resulting
in a large low luminance source of light
for the room.
One way to test for glare discomfort is to have the worker look at
their computer screen and be aware of any bright lights in their
peripheral vision. They the can use their hand to shield their eyes
like a baseball cap visor and note whether they sense an
immediate improvement in their comfort. They should try this 2-3
times. If they notice an immediate sense of improved comfort by
eliminating the lights from their peripheral vision, then they are
experiencing glare discomfort.
Solutions to glare discomfort
If bright lights are deemed to be contributing to discomfort, then
they should be removed or mitigated in some manner. There are
several ways in which they can be improved.
their computer screen and be aware of any bright lights in their
peripheral vision. They the can use their hand to shield their eyes
like a baseball cap visor and note whether they sense an
immediate improvement in their comfort. They should try this 2-3
times. If they notice an immediate sense of improved comfort by
eliminating the lights from their peripheral vision, then they are
experiencing glare discomfort.
Solutions to glare discomfort
If bright lights are deemed to be contributing to discomfort, then
they should be removed or mitigated in some manner. There are
several ways in which they can be improved.
- Turn off some of the offending fluorescent lights. Sometimes
it is a single fluorescent fixture in the ceiling which is just in
front of the person. Very often a single offending fixture can
be turned off without creating lighting deficiencies. - Fluorescent light fixtures can be retrofit with parabolic
louvers which direct the light straight down into the room.
The parabolic louver (the louver is the egg crate-like cover
that directs light into the room) directs the light from the
fluorescent tubes straight downward, hence it is not directed
into anyone's eyes. - Re-orient the work station so that bright lights are not in the
field of view. Sometimes the work desk can be rotated 90 or
180 degrees so that the fluorescent lights or bright windows
are not in the field of view. - Wear a visor. This is actually a very efficient way to eliminate
the brightness of overhead fixtures. A person can wear a visor
for a day or two as a test to determine the extent to which the
light problem alleviates discomfort at the end of the day. - Avoid bright reflective surfaces. In some work environments,
the desk tops are white. This results in the desk top surface
becoming a discomfort glare source. Desktops and other
furnishings should have a matte, medium reflective surface. - Use blinds or drapes on windows. This is often the most
difficult to implement because people like the views out of
windows. However, if the view out the window is considerably
brighter than the objects in the room (as it almost always is)
then the window is serving as a discomfort glare source. - Evaluate whether auxiliary lighting (for example a desk
lamp) on reference documents is causing glare discomfort. - Change the brightness of the screen. The brightness of the
screen should be adjusted to match the brightness of the
visual objects which immediately surround it. - Hang or erect partitions. Very often the offending light
sources can be eliminated from the field of view by erecting or
moving partitions.