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QSA Global, Inc.
40 North Avenue Burlington, MA 01803
888.272.2242
781.272.2000
qsa-global.com
Operations Manual
MAN-038 March 2019
Page 28 of 100
lock slide from the SECURED position into the EXPOSE position. The lock slide must be manually
pushed into the EXPOSE position prior to each radiographic exposure to enable operation of the remote
control.
Second, during termination of a radiographic exposure, the remote controls are used to retract the source
back into the gamma-ray source projector. When the source assembly is returned to the fully shielded
position within the gamma-ray source projector, the locking mechanism automatically secures the source
assembly, preventing the source from being inadvertently exposed from the fully shielded position. The
automatic securing mechanism allows movement of the gamma-ray source projector with the remote
controls attached at the job site while preventing inadvertent exposure of the source assembly.
For the third feature, the controls cannot be removed from the gamma-ray source projector locking
mechanism unless the source assembly has been returned to the fully shielded position within the
gamma-ray source projector.
The complete radiography system consists of the radiographic gamma-ray source projector containing
the source assembly, the remote controls, source guide tubes and collimators (beam limiters) whenever
possible.
The use of multiple source guide tubes must be a combined length shorter than the length of the remote
controls, e.g. if the remote controls are 25 ft (7.6 m) long, only 3 source guide tubes can be utilized for a
combined length of 21 ft (6.4 m). This consideration ensures the source assembly will be fully projected to
the source stop (exposure head).
The source assembly must never be projected until the equipment is properly connected and all
personnel have exited the restricted area.
Figure 5 - Cross-sectional view of the sealed source assembly in fully shielded position in the
radiographic gamma-ray source projector.