Specifications

D. VERIFICATION OF COMPLIANCE
Verify that the radiation output in step 2 is greater than or equal to 50 percent of
the radiation output in step 1.
.03 METHOD III - BRH/FDA COMPLIANCE TEST
A. GENERAL
The HVL determinations obtained from the following procedures are to be
compared with those illustrated in Table 5-1. The HVL in millimeters of
aluminum of the system being tested must be greater than or equal to the values
shown in Table 5-1.
B. EQUIPMENT
1. BRH/FDA compliance test standard with accessories.
2. Survey meter adapted for use with stand with an ion chamber.
3. Several sheets of aluminum, each having a thickness of 0.5 or 1.0
millimeter.
C. PROCEDURE
1. Attach the spacer, positioned out of the primary beam, to the test stand.
Center the stand on the table. Center the source over the stand and
bring the beam-limiting device down into firm contact with the spacer.
Select the MANUAL mode of operation (there must not be a cassette in
the cassette tray). Insert the beam-defining assembly in slot 1 of the
stand with the leaded side up (See Figure 5-1). Adjust the beam-limiting
device so that the X-Ray field slightly exceeds the aperture of the beam-
defining assembly. Mount the ion chamber at position B with the
chamber facing upward. Connect the chamber and meter with the cable
provided. Select a tube potential that is commonly used and is in the
highest kVp range of the X-Ray system.
2. With no added filtration in the beam, make an exposure and record the
reading. For all diagnostic X-Ray equipment, use Table 5-3 to determine
increments of filtration required to perform the half-value layer procedure.
Make an exposure and record the reading for each total thickness.
November 2005 ( 5 -6 ) Linear MC150-C Collimator
TABLE 5-3 HIGHEST DESIGN OPERATING RANGE