Fluke Biomedical 37-001 - Manual (Page 6)

Nuclear Associates 37-001
Operators Manual
1-2
C. Head Rotation and Pitch
By exercising these motions and returning to the zero settings, the accuracy of the zero indicator or
interlock can be demonstrated by observing the coincidence of the machine crosshairs with the
TEL-ALIGN.
D. Isocenter
By rotating the gantry from 0° to 90°, 180° and 270°, any variation of coincidence can be tracked by
the projection of the crosshairs and corresponding crosses on the TEL-ALIGN.
E. Side Lights and/or Back Pointer
Projection and intersection of the corresponding crosses at 0°, 90°, 180° and 270° will demonstrate
alignment.
F. Light Field vs. Radiation Field
Ready-pack film is placed under the TEL-ALIGN gauge, and an appropriate exposure is given. The
coincidence of the radiation field edges, with the embedded lead markers in the gauge, can then be
verified on the developed film.
1.5 Evaluation Results
The allowed tolerance for alignment of the above parameters is usually of the order of 1-2 mm. However,
the manufacturer's specifications should be consulted for a specific machine. When the tests demonstrate
misalignment, adjustments can be made to the unit with the TEL-ALIGN in position on the table.