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Module 7Module 7
Protection Against Occupational Protection Against Occupational ExposureExposure
IAEA Post Graduate Educational Course in Radiation Protection and safety of Radiation Sources
Module 7 : Industrial Radiography 2
Aims and ObjectivesAims and Objectives
Be familiar with typical industrial Be familiar with typical industrial radiography accidentsradiography accidents
Understand specific contributing factorsUnderstand specific contributing factors Be aware of lessons learned from past Be aware of lessons learned from past
accidentsaccidents
Module 7 : Industrial Radiography 3
ContentsContents
Case histories describedCase histories described Consequence of each accident Consequence of each accident Lessons learnedLessons learned
Module 7 : Industrial Radiography 4
Gamma Site Radiography Lost SourceGamma Site Radiography Lost Source
550 GBq iridium-192550 GBq iridium-192 source became detached, fell from source became detached, fell from
guide tubeguide tube 5 days before loss was realised5 days before loss was realised 78 persons irradiated78 persons irradiated doses ranged from 11 mSv to 150 mSvdoses ranged from 11 mSv to 150 mSv
Module 7 : Industrial Radiography 5
Gamma Site Radiography Lost SourceGamma Site Radiography Lost Source
•Incorrect use of monitor
•inadequate monitoring
Module 7 : Industrial Radiography 6
Gamma Site Radiography Defective Gamma Site Radiography Defective EquipmentEquipment
3.2 TBq iridium-1923.2 TBq iridium-192 source jammed in exposed positionsource jammed in exposed position no emergency equipmentno emergency equipment no local rules or exposure warningsno local rules or exposure warnings IAEA assistance in source recoveryIAEA assistance in source recovery 7 persons involved in recovery, all doses 7 persons involved in recovery, all doses
< 1.0 mSv< 1.0 mSv
Module 7 : Industrial Radiography 7
Gamma Site Radiography Defective Gamma Site Radiography Defective EquipmentEquipment
lead container
guide tube
Module 7 : Industrial Radiography 8
Gamma Site Radiography Defective Gamma Site Radiography Defective EquipmentEquipment
source activity should be optimized- > 1.8 TBq for source activity should be optimized- > 1.8 TBq for site work should be justifiedsite work should be justified
reasonably foreseeable accidents should be reasonably foreseeable accidents should be highlighted in prior safety assessmentshighlighted in prior safety assessments
adequate maintenance of ancillary equipment is adequate maintenance of ancillary equipment is essentialessential
site radiography requiressite radiography requires
X-Ray Site Radiography Localised X-Ray Site Radiography Localised ExposureExposure
X-Ray Site Radiography Localised X-Ray Site Radiography Localised
Exposure160 kV x-raysExposure160 kV x-rays No exposure warningsNo exposure warnings Fingers exposed to primary beam for ~ 10 Fingers exposed to primary beam for ~ 10
secondsseconds Localised dose of ~ 60 SvLocalised dose of ~ 60 Sv
Module 7 : Industrial Radiography 10
X-Ray Site Radiography Localised X-Ray Site Radiography Localised ExposureExposure
periodic checks on safety systems are periodic checks on safety systems are essentialessential
radiation monitoring is essentialradiation monitoring is essential local rules must be observedlocal rules must be observed personal alarm monitors can lessen the personal alarm monitors can lessen the
consequences of an accidentconsequences of an accident
Module 7 : Industrial Radiography 11
Gamma Site Radiography Gamma Site Radiography Disconnected SourceDisconnected Source
1100 GBq iridium-1921100 GBq iridium-192 source became disconnected from the source became disconnected from the
drive cabledrive cable source picked up by a member of the source picked up by a member of the
public and taken homepublic and taken home source “lost” from March to Junesource “lost” from March to June 8 persons died as direct result from 8 persons died as direct result from
Adherence to established safety procedures Adherence to established safety procedures would have prevented most accidentswould have prevented most accidents
Safety may be compromised if regulatory Safety may be compromised if regulatory controls are not in placecontrols are not in place
Systematic audits by management help to ensure Systematic audits by management help to ensure that level of knowledge and performance of that level of knowledge and performance of radiographers is maintainedradiographers is maintained
A poor safety culture can result in degradation of A poor safety culture can result in degradation of safety systems and proceduressafety systems and procedures
Deficient training is contributory in the majority Deficient training is contributory in the majority of accidentsof accidents
Adherence to established safety procedures Adherence to established safety procedures would have prevented most accidentswould have prevented most accidents
Safety may be compromised if regulatory Safety may be compromised if regulatory controls are not in placecontrols are not in place
Systematic audits by management help to ensure Systematic audits by management help to ensure that level of knowledge and performance of that level of knowledge and performance of radiographers is maintainedradiographers is maintained
A poor safety culture can result in degradation of A poor safety culture can result in degradation of safety systems and proceduressafety systems and procedures
Deficient training is contributory in the majority Deficient training is contributory in the majority of accidentsof accidents
Module 7 : Industrial Radiography 14
Where to Get More InformationWhere to Get More Information