DAILY INSPECTION INSTRUCTIONS

Figure 3.1 Source assembly and remote control cable connectors

2 Exposure Device

The source assembly is shown in the stored position in a titanium or ‘S’ tube at the center of the depleted Uranium shield of the exposure device. (See figure 3.2)

A remote control unit is shown with its control cable connector coupled to the source assembly.

High density depleted Uranium shielding is used in the exposure device to provide good radiological protection with minimal weight.

A shielded outlet port cover mechanism permits a secure attachment of source guide tubes (projection sheaths) without an elevation of radiation levels. The outlet port mechanism will not allow the source assembly to be projected outside of the exposure device unless a source guide tube has been properly attached to the outlet port. A three-step connection is accomplished by completion of the following steps:

1Pull and rotate the spring-loaded outlet port cover a quarter turn (from a 12 o’clock to a 3 o’clock position) in a clockwise direction. This action moves the protective cover away from the outlet port to permit attachment of a source guide tube.

2A bayonet-style fitting of the source guide tube is inserted into the outlet port and rotated a quarter turn (from a 12 o’clock position to a 9 o’clock position) counter-clockwise. A complete insertion and counter-clockwise rotation of the source guide tube fitting releases the lock and an internal shielding rotor of the outlet port.

3Rotate the spring-loaded cover an additional 60 degrees (from a 3 o’clock position to a 5 o’clock position) in a clockwise direction until it stops. This last movement moves the outlet port shield out of position and aligns a pass-through opening on the rotor with the ‘S’ tube and outlet port while simultaneously securing the source guide tube fitting to the outlet port.

The design permits attachment of the source guide tubes without an elevation of radiation intensity at the outlet port, minimizing the radiation exposure to the radiographer’s hands. The sealed source assembly cannot be exposed out of the exposure device unless a positive connection of the source guide to the device has been accomplished.

The exposure device’s locking mechanism provides three main safety features for the radiographer during radiographic operations.

3.2

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Sigma projetor manual Exposure Device, Source assembly and remote control cable connectors