Figure 8-4. Fourth quadrant.
EVALUATION AND INTERPRETATION
a. Determine the average illumination level for each viewbox (all readings
should be the same).
b. Do not accept a variation of illumination between individual quadrants if it
Fifteen percent in five groups of viewboxes.
Twenty percent in group-to-group variations.
a. Replace illuminator lamps:
Every year if used 8 hours per day.
More frequently if used more than 8 hours per day.