Specifications

Those authorized to operate, test, participate in or supervise the operation of the
equipment must be thoroughly familiar and comply completely with the currently
established safe exposure factors and procedures described in publications such as
Sub-Chapter J of Title 21 of the Code of Federal Regulations, “Diagnostic X-Ray
Systems and their Major Components,” and the National Council on Radiation Protection
(NCRP) No. 33, “Medical X-Ray and Gamma-Ray Protection for Energies up to 10 Me
V-Equipment Design and Use,” as revised or replaced in the future.
Failure to observe these warnings may cause serious, genetic or potentially fatal bodily
injuries to the operator or those in the area.
XR 8-2.09 BEAM QUALITY (HALF-VALUE LAYER [HVL])
REQUIREMENT- The minimum beam quality requirements listed in Table 5-1 shall be
met. [See 21 CFR 1020.30 (m).]
.01 METHOD I - VISUAL DETERMINATION OF HALF-VALUE LAYER (HVL)
A. General
The above HVL requirement will be considered to have been met if it can be
demonstrated that the aluminum equivalent of the total filtration in the primary
beam is not less than that shown in Table 5-2.
B. Equipment
None is required.
Table 5-1 MINIMUM BEAM QUALITY REQUIREMENTS
Kvp Range Measured kVp HVL (mmAl*)
Below 50.................. ...............30 0.3
40 0.4
49 0.5
50 to 70................... ...............50 1.2
60 1.3
70 1.5
Above 70................. ...............71 2.1
80 2.3
90 2.5
100 2.7
110 3.0
120 3.2
130 3.5
140 3.8
150 4.1
*Type 1100 aluminum alloy as given in Aluminum Association Publication
No. ASD-1, Aluminum Standards and Data.
November 2005 ( 5 - 4) Linear MC150-C Collimator