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Types of Radiation Sources and Procedures using Inspection Devices 1
Types of Radiation Sources and Procedures using Inspection
Devices
Simon COENEN Technical Meeting on Implementation of the requirements in the International Basic Safety Standards in relation to Non-Medical
Human Imaging
IAEA, Vienna, 17-20 January 2017
Types of Radiation Sources and Procedures using Inspection Devices
• Introduction – Definitions
• Types of radiation sources
o X-ray
o g-sources
o b-sources
o n-sources
o Types of Devices
o Concluding Remarks
Types of Radiation Sources and Procedures using Inspection Devices 2
Introduction - Definitions
• Inspection Imaging Device
– Designed for imaging persons or cargo
– To Detect concealed objects on or within the human body or cargo
• Inspection device
– Device using ionising radiation to Detect presence of drugs or explosives through detection of characteristic responses.
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Imaging Backscatter Vs Transmission
• Backscatter
– Uses radiation that is scattered or deflected to produce an image
– Lower dose
– Allows for scanning of concealed objects
• Transmission
– Conventional means where X-rays pass through target to create an image
– Allows for more detail and in depth imaging
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Types of Radiation Sources – X-Rays • Generated by
– X-ray tube : 70 – 450 kVp
– Linear Accelerator : 2 – 9 MeV
• Penetration Depth (depending on energy and density of the material)
– X-ray : < 100 mm
– Linear Accelerator : 200 – 400 mm
• Need for
– Electricity
– Shielding
• For Linear Accelerators
– Production of neutron and neutron capture reactions
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Types of Radiation Sources – g sources
• Uses g rays (137Cs, 60Co), typical activity up to 100 GBq.
• Penetration depth : 150 mm.
• Specific shielding is needed : up to 30 mSV/h at 1 m.
• Specific radiation protection procedures needed at all times.
• Radioactive decay calls for regular replacement of the source.
• Proper disposal of the source and end of life required.
• More and more replaced by X-ray technology.
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Types of Radiation Sources – b sources
• Electron capture device
• Detection of trace quantities of explosives and drugs by ion mobility spectrometry
• 63Ni source (555 MBq), low energy b
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Types of Radiation Sources – n sources
• Used for some applications
• Identifying specific (low Z) materials in cargo
• Often requires extensive shielding and radiation protection procedures
• Seen as a complementary tool with X-ray scanning
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Types of Inspection Devices Post room & Baggage scanners
o X-rays : 80 kVp – 160kVp
o Fixed systems
o Inspection zone : prevent access to screening area
o Interlocks : to prevent access to radiation areas
o Dose rate outside the machine is very low
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Types of Inspection Devices Bottle Scanners
• Multispectral X-rays
• Compared with a database of “threat” items
• 160 kVp
• Interlocks to prevent acces to radiation area
• Dose rate outside instrument < 1µSv/h at 10 cm
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Types Inspection Devices Handheld Backscatter
• Open beam, low energy (70 kVp), low dose rate backscatter X-rays
• Detection of organic threats, contrabands and explosives
• Exclusion zone in front of device
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Types of Inspection Devices Handheld Transmission
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• 40-70 kVp
• Live X-ray video
Types Inspection Devices Portable X-ray Units
• On-site examination
• Up to 300 kVp, pulse mode X-rays
• Exclusion zone around object needed
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Types Inspection Devices Narcotics and Explosives Detection
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• Detect trace quantities of explosives or drugs
• Uses 63Ni b source
• Based on swab or air sampling
Types Inspection Devices Vehicle and Cargo Scanners
• X-rays > 160 keV, often produced with linear accelerators
• Energy need depends on the size of the vehicle or cargo
• Fixed or relocatable systems
• Drive through systems Vs Mobile Systems
• Exclusion zones
• Specific shielding an radiation protection issues
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Fixed Cargo Scanners
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• High Energy (9 MeV)
• Large exclusion zone
• Driver not allowed in vehicle during inspection
Relocatable scanners
• Lower energy (~6 MeV)
• Require dedicated and prepared area
• Exclusion zone needed
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Mobile Scanners
• Low energy (~3 MeV)
• Built on a truck
• Exclusion zone needed in function of energy and size
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Drive Through Systems
• Higher throughput, driver can remain in vehicle
• System to avoid exposing driver (but no image of driver cabine)
• Energy : 3 – 6 MeV
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Questions ?
Even when in a hurry do not behave like this passenger
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