Fluke Biomedical 07-621 - Manual (Page 9)

Specifications
Procedure
1.8 Specifications
Capabilities: Illuminance in lux; luminance in cd.m
2
(Nit).
Readout: Three-digit LED display.
Range: 00.1 to 999000.
Accuracy: Within 7%
± 2 digits of full-scale range for 2500°k to 5400°k light sources.
Sensor: Silicon photodiode with photometric filter
Spectral Response: Close match to CIE photoptic response curve
Batteries: 1.5V, Type A-76 alkaline button cells, or silver oxide types, MS-76, 10L 14, RW-42, 357.
Size: 10 x 7 x 2.5 cm
Weight: Approx. 4 oz. (110g).
Recommended Operating Conditions: 5°C to 40°C (41°F to 104°F), maximum 95% relative humidity, non-
condensing .
Supplied with: Case, neck cord.
1.9 Suggested Viewbox Procedure
Viewboxes should be checked for uniformity on a semi-annual basis. Each viewbox should be checked in
relation to the other viewboxes in the panel. Take a 12-inch ruler, and attach it to the photometer using a
rubber band, so that the aperture receptor for luminance is at the 9-inch mark. There should be a 9-inch
reproducible distance when taking readings. Before taking any measurements on a viewbox, the ambient
room lighting should be the same as when radiographs are being read. When testing uniformity from one
viewbox to another, place the end of the ruler at the center of the viewing panel, and take a reading.
Follow the same procedure at each of the view boxes. The luminance of each of the viewboxes should
not deviate from one to the other by more than 15%.
When checking the uniformity of a single viewbox, visually divide the viewing panel into four quadrants.
Place the end of the ruler at the center of each of the quadrants, and take a reading. The readings from
each of the four quadrants should not deviate by more than 15%.
If the viewboxes do not meet this criteria, they should be dismantled and cleaned. Once this is done,
repeat the test. If the results are the same, then all of the light bulbs should be replaced. The typical
viewbox luminance should be approximately 1500 Nit. Viewboxes used for viewing mammograms should
have a luminance of approximately 3500 Nit.
1.10 Routine Cleaning
CAUTION
Do Not Immerse the Model 07-621 Precision
Photometer in liquid. The unit is not waterproof.
Liquid could damage the circuits. The unit should
be kept clean and free from dirt and contamination.
The unit may be cleaned by wiping it with a damp
cloth, using any commercially available cleaning or
decontamination agent.