Sigma projetor manual Retracting, Confirmatory Survey, Locking the Exposure Device

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OPERATING INSTRUCTIONS

STEP 4

Retracting

At the end of the required exposure time, set the brake to OFF and rapidly turn the crank handle in the RETRACT (clockwise) direction until it no longer moves. You may hear the lock slide ‘click’ back into its original position depending on the ambient noise level at the job site. From the control crank you may be able to observe the GREEN MARKING on the slide bar.

Apply a slight amount of forward pressure on the crank handle as if to expose the source to ensure that the positive locking mechanism has actuated.

Allow the crank handle to return to a neutral position, thereby relieving any tension (force) on the control cable that would cause source movement when unlocking the projector. At this point the source cannot be moved out of the stored position.

In the unlikely event the lock slide moves toward the lock position before the source is fully stored in the exposure device, turn the crank handle in the RETRACT (clockwise) direction until it stops turning. (The lock slide is designed to lock on the stop ball, not the control cable). Do not use excessive force. The source assembly will be in the exposure device but not in the fully shielded position. Approach the exposure device, from the rear, with a survey meter. The survey meter will measure approximately 400 µSv/hr (40 mR/hr) at the rear plate of the exposure device when a 3.7 TBq (100 Ci) Ir-192 source is in use.

CAUTION

Remain clear of the front of the exposure device (outlet port side) to minimize personal exposure. Reset the lock slide to the open position. Return to the control crank and turn the crank handle in the RETRACT (clockwise) direction and store the source assembly in the normal manner.

The odometer (if supplied) should read approximately zero when the source assembly has returned to the projector.

Confirmatory Survey

Approach the exposure device while observing the survey meter – observe the GREEN MARKING on the lock slide and survey the exposure device. The survey meter should indicate the same radiation level as observed before the exposure. Note particularly the outlet port reading.

Survey the entire length of source guide tube with the survey meter. If the meter shows a sharp increase, the source is exposed or incompletely shielded.

If the source is still exposed, attempt to store it properly by cranking the source a short distance towards the exposure head and retracting it, repeating if necessary.

Locking the Exposure Device

When the source assembly is properly stored in the projected, rotate the selector ring from the OPERATE position to the LOCK position and secure it with the plunger lock.

Remove and safeguard the key.

WARNING!

If after several attempts to return the source assembly, the selector ring cannot be rotated to the lock position (do not use excessive force) or the lock slide is not actuated, one must suspect an accident in which the source assembly may have become disconnected or stuck outside the projector, giving rise to a very high radiation field. Treat the situation as an EMERGENCY.

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Contents MAN-027-May Operating and Maintenance ManualTime Page Front View Exposure Device Description Model 880 Delta authorized contents Standard Source AssemblyModel 880 Sigma authorized contents ApplicationsModel 880 Omega authorized contents Model 880 Elite authorized contentsSource output Selected attenuation dataControl Specifications Complete Remote Control Assemblies Source Guide Tube with source stopSource Guide Tube Extension Weight of Exposure Device Type BU Certification Exposure Device Specifications Manufacturer LengthWeight of Depleted Uranium Shield Primary Application WidthDevice Operating Temperature Range Maintenance RequirementsSource Assembly ConstructionWarranty and Limitation of Liability Restricted Area Job site safety precautions InstrumentsDistance ShieldingSource Guide Tube projection sheath Layout Exposure Device SurveySimultaneously pull and rotate Remote Control Conduit Layout Unlock the plunger lock with the key Important Warning Checks Before Exposure of the Source 1Unlocking Projecting Retracting Confirmatory SurveyLocking the Exposure Device Source guide tubes Dismantling equipment Remote control unitSurveying StorageIntroduction Operational Features Source AssemblyExposure Device Source assembly and remote control cable connectorsDaily Inspection Instructions Exposure Mode Transit ModeDaily Inspection of the Exposure Device Daily Inspection of the SystemDaily Inspection of the Source Guide Tubes Daily Inspection of the Remote ControlsImportant Warning Remote Control InspectionControl Cable Inspection Control Conduit InspectionImportant Reminder Maintenance Instructions Radiographic Exposure Device Routine Quarterly Maintenance Requirements Remote ControlsMisconnect Test Annual Maintenance Requirements Routine Quarterly Maintenance RecordsLeak Test for Depleted Uranium DU Leak Testing Leak Test of the Radioactive Sealed SourceAnnual Maintenance for the Model 880 Series Exposure Devices Model 880 Series Annual Maintenance Requirements Maintenance Instructions Maintenance Instructions Maintenance Instructions Remote Control Maintenance Requirements Annual Maintenance for the Remote ControlsMaintenance Instructions Maintenance Instructions Re-assembly of the Remote Control Unit Source Guide Tube Maintenance Quarterly and Annual Maintenance for Source Guide TubesMaintenance Instructions Considerations of Safety Class a Items Annual Maintenance RecordsRear Plate Assembly Rear Plate Assembly Front Plate Assembly Front Plate Assembly Control Assemblies Source Guide Tubes Control Assemblies 222 Sample Transportation Instructions Transport PackageReceipt of Radioactive Material Shipment of Radioactive Material Maximum Radiation Sample Transportation Instructions Sample Transportation Instructions Shipment of Empty Uranium Shielded Containers Sample Transportation Instructions Carriage of Radioactive Material Sample Transportation Instructions Radioactive material transport checklist Alarm ratemeter Area alarmApparatus for industrial gamma radiography Automatic securing mechanismExposure head Remote controlLocked position Maximum ratingSource holder Source changersWorking position Training EmergenciesUnited States Regulations Access to Restricted AreasEU Regulations Personnel MonitoringDisposal Abc