SIGMA projetor - Manual (Page 25)

DAILY INSPECTION INSTRUCTIONS
3.3
First, the locking mechanism requires a deliberate action to enable exposure of the source assembly.
This is accomplished by coupling the control cable connector to the source assembly connector, coupling
the remote control connector to the exposure device locking mechanism and then pushing a 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 exposure device. When the source assembly is returned to the fully shielded position within
the exposure device, 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 exposure device 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 exposure device locking mechanism
unless the source assembly has been returned to the fully shielded position within the exposure device.
The complete radiography system consists of the radiographic exposure device 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 3.2 Sealed source in fully shielded position of radiographic exposure device.
Control Cable Exposure Device
Source Assembly
Sealed Source
Remote
Control Crank
Locking
Mechanism
Shield Outlet Port Source Guide
Tubes