DAILY INSPECTION INSTRUCTIONS

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.

Source Assembly

Control Cable

Exposure Device

Sealed Source

Remote

Locking

Shield

Outlet Port

Source Guide

Control Crank

Mechanism

 

 

Tubes

Figure 3.2 Sealed source in fully shielded position of radiographic exposure device.

3.3

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Sigma projetor manual Daily Inspection Instructions