Figure 5-3. Be sure to put on
Figure 5-4. Observe the image.
your lead apron.
5-4.
EVALUATION AND INTERPRETATION
a. After locking the assembly in place, you must measure the distance between
the two metal objects (the metal strips, quarters, or whatever you used). This distance
equals the distance between the source and the tabletop.
b. The minimum range, usually, is 17 to 20 inches with a one-inch leeway. In
other words, 16 inches would be all right, but 15 inches or less would not be acceptable.
In such a case, the patient would receive too much radiation. If the distance is greater
than 21 inches, the patient would produce a less than optimal exam or study (see figure
5-5).
NOTE:
A distance of 12 inches is acceptable for portable units.
c. Record your findings on a data sheet.
MD0062
5-4