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Kamel ABBASEuropean Commission, Joint Research Centre
Institute for Transuranium Elements, Nuclear Security Unit Via E. Fermi, 2749, I-21027 Ispra, Italy
tel. +39-0332-785673, e-mail: [email protected]
Safety and Security aspects on Radioactive Sources
7777thththth International Summer International Summer International Summer International Summer School on School on School on School on NuclearNuclearNuclearNuclearDecommissioning and Waste Management andDecommissioning and Waste Management andDecommissioning and Waste Management andDecommissioning and Waste Management and
Ispra, 14Ispra, 14Ispra, 14Ispra, 14----18 18 18 18 SeptemberSeptemberSeptemberSeptember 2015 2015 2015 2015
School organised by:
And supported by:
The Nuclear Security Summit 2014 focused on strengt hening security and preventing terrorists, criminals and all other unauthorised ac tors from acquiring nuclear material
that could be used in nuclear weapons, and other ra dioactive materials that could used in radiological dispersal devices.
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Content
�Basic of radiations and their detection
� Exposure to radiation and their effects on human
�Safety and Security regime for radioactive sources (RS)
RS Categories, their utilisation, Inventory, Physical Protection, Detection equipment
used for RN border monitoring, …
� Example of incident involving a RS
� EU legal framework for 2S of RS
�Conclusion
Radioactive SourceIAEA definition
“radioactive source” means radioactive material that is permanently sealed in a capsule or closely bonded, in a solid form and which is not exempt from regulatorycontrol.
It also means any radioactive material released if the radioactive source is leaking or broken, but does not mean material encapsulated for disposal, or nuclearmaterial within the nuclear fuel cycles of research and power reactors.
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Tables of Elements and Nuclides
Uranium (U): 92 protons; average mass: 238Uranium (U): 92 protons; average mass: 238Uranium (U): 92 protons; average mass: 238
Penetration of radiations
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Radiation Detection
• The energy with which they are emitted is distinct (signature!) . For example Am-241 emits alpha-particles of 5.49 MeV (86%) and 5.44 MeV (13%).
• Very easy to shield Very difficult to detect .
Alpha particles
Beta Particles
• The energies of beta-particles form a continuum
• Not a signature ! Difficult to use for identifying radioactive materi al!
• Easy to shield Direct detection is difficult.
Gamma Rays
Neutrons Conversion:
Detectionneutrons Charged particles
Some Units
The curie (Ci) is an older, non-SI unit of radioactivity, Bq1 Ci = 3.7 x 1010 Bq ≈ activity of 1 g 226Ra
The rad is an older, non-SI unit of the absorbed dose1 Gy (1 joule/kg) = 100 rad
The rem is an older, non-SI unit of the dose equivalent (absorbed dose per a quality factor)
1 Sv = 100 rem
The dose rate is defined by the dose equivalent per exposure time (example uSv/h)
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Man-Made Sources of Radiation
Humans are exposed to man-made radiation. The major sources are
illustrated below. By far, most of the dose comes from medica l x-rays.
Radiation Background
The worldwide average background dose for a human b eing is about 2.4
mSv per year
Food40K
pCi/kg
226RapCi/kg
Banana 3,520 1
Brazil Nuts 5,600 1,000-7,000
Carrot 3,400 0.6-2
White Potatoes 3,400 1-2.5
Beer 390 ---
Red Meat 3,000 0.5
Lima Beanraw
4,640 2-5
Drinking water --- 0-0.17
Radiation from food products
50% radioactive gases indoor
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Stochastic effects
� Associated to exposures to low levels of radiation over a long time.
Deterministic effects
� Associated to exposures to high levels of radiation over a short time. The higher is the (high) dose, the higher will be the severity of the effect.
� 1 – 2.5 Sv: nausea, persistent fatigue, partial epilation, fatality ≈ 10% after 30 days
� 2.5 – 4 Sv: nausea, vomiting, loss of hair, massive lost of white blood cells, fatality ≈ 50% after 30 days
� 6 – 10 Sv: bone marrow destroyed, fatality close to 100% after 14 days
� 2.4 mSv/year: world average dose due to background, 1 mSv/year: maximum dose uptake for the “non-exposed workers” (public), 20 mSv/year: maximum dose uptake (in addition to the background) for the “exposed workers”
� 1 week in mountains at 2000 m: 0.03 mSv, Flight Paris – New York: 0.02 mSv
Effects of radiation on human health
Response to a detection event
If a radioactive source is discovered, appropriate protection measures are required to protect individuals from exposure:
1. Protection of the first responders
2. Protection of the public and the environment
Usually, expose to radiation can be reduced to an acceptable minimum by :
Nuclear security or safety event
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Radiation Exposure Reduction
There are three ways to minimize the risk of radiation exposure:
� Time: reduce the time of the exposure as much as possible.
� Distance: the further away from the source of radiation, the better.
� Shielding: In an exposed area, choose the appropriate shielding!
In order to stay below the dose uptake limit it is recommended to fix an intervention threshold:
• If the dose rate at 1 meter from the source is lower than 0.1 mSv/h, it is safe to approach the source for localization and categorization
• Above 0.1 mSv/h at 1 meter do not intervene, but establish a protection boundary such that nowhere the dose rate is > 0.02 mSv/h and call expert responders
Radiation Exposure Reduction
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• Radiological Dispersion DeviceAny radioactive sources used in industry, medicine, …These are mostly beta/gamma emitters, few pure beta (H-3, Sr-90)Generally high energy gamma (detectable, difficult to mask)
• Nuclear Devices• Nuclear Weapon based on HEUHEU is an alpha/gamma emitter.Low energy gamma (easily shielded)
• Nuclear Weapon based on PuPu is an alpha/beta/gamma/neutron emitter.Low energy gamma (easy to shield) + neutron
Nuclear SecurityRDD and ND
� Approved by the IAEA Board of Governors in Sep. 2003
� Published in Jan. 2004
� First international document on the security of
radioactive sources
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1487_web.pdf
Code of Conduct on the Safety and Security of Code of Conduct on the Safety and Security of Code of Conduct on the Safety and Security of Code of Conduct on the Safety and Security of RSRSRSRS
� Member States recognized the need of such a document to provide advice on how to
protect individuals, society and the environment from the harmful effects of possible
accidents and malicious acts involving radioactive sources
� Today, there is open-source evidence proving the intent of non-State actors or groups
to acquire and use sources for Radiological Dispersion Devices “dirty bombs”
The CoC provides guidance for national governments to improve their legislation and
regulations for the security of sources
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Some points of the CoC
� States should establish a national registry of radioactive sources for Category 1 and 2, at a minimum
� States should use the guidance in the Code of Conduct for the import and export Category 1 & 2 sources
� States should ensure that imports and exports are conducted consistent with existing relevant international standards
� Trans-shipment through a State should be conducted consistent with existing relevant international standards and maintain continuity of control
Examples of Practices Using Radioactive SourcesCategory 1
Irradiators Used to sterilize food, cosmetics, medical products and supplies, and for other specialized applications such as research applications or for blood irradiation.
cobalt-60 56 to 560,000 TBq
caesium-137 37 to 190,000 TBq
Teletherapy Used for cancer therapy and are commonly found in medical institutions, such as hospitals or clinics.
cobalt-60 37 to 560 TBq
caesium-137 19 to 56 TBq
Fixed multi-beam teletherapy
Used to focus gamma radiation from an array of over 200 sources on brain lesions (gamma knife). These are commonly found in hospitals or clinics.
cobalt-60 150 to 370 TBq
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Industrial radiography
Used to test the integrity of various materials, as well as for testing welds in pipes and tanks in the petrochemical industry.
Cobalt-60 0.41 to 7.4 TBq
Iridium-192 0.19 to 7.4 TBq
Selenium-753 TBq
Ytterbium-169 0.093 to 0.37 TBq
Thulium-170 0.74 to 7.4 TBq
High/medium dose ratebrachytherapy
Used for cancer therapy and are commonly found in medical institutions, such as hospitals or clinics.
Cobalt-60 0.19 to 0.74 TBq
Caesium-137 0.11 to 0.3 TBq
Iridium-192 0.11 to 0.44 TBq
Examples of Practices Using Radioactive Sources Category 2
Fixed industrial gauges
Used for process control; for measurement of flow, volume, density, or material presence; and may be placed in locations unsuitable for continuous human presence
cobalt-60 0.0037 to 0.37 TBq
caesium-137 0.00011 to 1.5 TBq
californium-252
0.0014 TBq
Well logging gauges
Used in areas where exploration for minerals is occurring, such as coal, oil, natural gas
americium-241/beryllium
0.019 to 0.85 TBq
caesium-137 0.037 to 0.074 TBq
californium-252
0.001 to 0.0041 TBq
Examples of Practices Using Radioactive SourcesCategory 3
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Support of IAEA to national regulatory bodies to establish nuclear security regimes
RAIS: RAIS: RAIS: RAIS:
General Principles in the CoC
� Radioactive sources should be safely managed and securely protected during their
useful lives and at the end of their useful lives
� States should promote safety culture and security culture for radioactive sources
� Establish and maintain an effective national legislative and regulatory framework
� Ensure appropriate training for the regulatory body, and law enforcement and
emergency agencies
� Define domestic threat and assess vulnerability based on loss of control or malicious
acts involving radioactive sources
� Establish a National Registry for Category 1 and 2 sources
� Share information concerning loss of control and incidents with potential transboundary
implications
� Promote awareness of orphan sources and implement measures to monitor and
recover orphan sources
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Role of the Regulatory Body
� Establish import-export controls
� Establish a registry of radioactive sources
� Coordinate with other governmental bodies
� Establish criteria for intervention in emergencies
� Require a security plan or assessment, as appropriate
� Agreements to return disused sources to a supplier
� Measures to determine the trustworthiness of individuals managing
radioactive sources
� Require confidentiality of source security information
Physical Protection
� A security system comprises people, procedures and equipment
� Detection, Delay, and Response work together to defeat the adversary
� Timely detection enables response force to arrive in time to interrupt
the adversary
� Response force should be
Sufficient to defeat the adversary
� The level of required protection
should be commensurate with
the consequences
13
Some other IAEA publications addressing safety and security of Some other IAEA publications addressing safety and security of Some other IAEA publications addressing safety and security of Some other IAEA publications addressing safety and security of
radioactive materialsradioactive materialsradioactive materialsradioactive materials
Code of ConductCode of ConductCode of ConductCode of Conduct Nuclear Security SeriesNuclear Security SeriesNuclear Security SeriesNuclear Security Series
NSS 11: Security of Radioactive Sources
NSS 14: Nuclear Security Recommendations
on Radioactive Material
and Associated Facilities
NSS 15: Nuclear Security Recommendations on Nuclear and other material out of Regulatory Control
It provides recommendations to a State for the detectionand assessment of alarms and alerts and for a gradedresponse to criminal or unauthorized acts with nuclearsecurity implications involving nuclear or other radioactivematerial out of regulatory control
Detection of Radioactive Materials at Borders, IAEA-TECDOC-1312, 2002Borders Monitoring is an essential component of an overall strategy to ensure that such materials do not fall into the hands of terrorist groups and tho se criminal organizations that would supply them.
Shipments of radioactive materials warrant the attention of law enforcement and regulatory agencies to ascertain legality, and to prevent diversion and illicit trafficking .”
Some other IAEA publications addressing safety and security of Some other IAEA publications addressing safety and security of Some other IAEA publications addressing safety and security of Some other IAEA publications addressing safety and security of
radioactive materialsradioactive materialsradioactive materialsradioactive materials
Detection of Radioactive Materials at Borders, IAEA-TECDOC-1312, 2002
Borders Monitoring is an essentialcomponent of an overall strategy toensure that such materials do notfall into the hands of terroristgroups and those criminalorganizations that would supplythem.
Shipments of radioactive materialswarrant the attention of lawenforcement and regulatoryagencies to ascertain legality, and toprevent diversion and illicittrafficking
Guidance on the import and export of radioactive sources (2012)
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International Catalogue of Sealed Radioactive Sources andDevices (IcSRS) a database of Manufacturers of Source anddevices by IAEA
help identify source/device model based on available information (isotope, size, shape, label, manufacturer).
link isotope activity with source model with device model with manufacturer/distributor.
help finding out where the source/device was manufactured.
help finding out if a source could be dangerous.
What is it for…?
https://nucleus.iaea.org/Pages/icsrsd.aspx
RN detection equipment e.g. Border Monitoring
Radionuclide Identifier
Neutron Search Device
Personal Radiation Detectors
Radiation Portal Monitor
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Goiania orphaned source dispersal, 1987
• A private radiotherapy institute moved to new premises leaving in place an unsecured caesium-137 teletherapy unit.
• Two scrap collectors, not knowing what the unit was, removed the source assembly from the radiation head of the machine, and took it home.
• They tried to dismantle, and the source capsule was ruptured, and the contamination of the environment ensued.
• The remnants of the source assembly were sold to a junkyard owner.
• He noticed that the source material glowed blue in the dark. People were fascinated by this, friends and relatives came to see the phenomenon.
• Fragments of the source were distributed to several families.
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Goiania orphaned source dispersal, 1987
• By five days a number of people were showing gastrointestinalsymptoms arising from their exposure to radiation.
• The symptoms were not initially recognized as being due toirradiation.
• The wife of the junkyard owner finally suspected the scrap metalto be the cause. She took the remains of the source by bus in aplastic bag to a hospital, and the physician there rightlysuspected that it was dangerous.
• A local physicist was the first to assess the scale of accident andtook actions on his own initiative to evacuate 2 contaminatedareas.
• At the same time the authorities were informed.30
16
Goiania orphaned source dispersal, 1987
Police, fire and civil defense forceswere mobilized and specialists weredispatched from Rio de Janeiro andSao Paulo to Gioania.
The nearby Olympic stadium had beendesignated as a staging area forisolating patients and screening othersfor contamination.
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Medical aspects:� 112,000 persons were monitored
� 249 of these had external / internal contamination (up to 7 Gy)
� 129 of these had both external and internal contamination
� 49 of these were admitted to hospital
� 20 of these needed intensive medical care
� 10 of these were in critical conditions
� 4 of these died (within four weeks) and one had to have the forearm amputated
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Goiania orphaned source dispersal, 1987
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Goiania orphaned source dispersal, 1987
• In total 85 houses were found to have significant contamination.
• 200 individuals were evacuated from 41 of them.
• 7 houses were demolished, the rest were decontaminated.
• Topsoil was removed from contaminated sites, surfaces were covered with clean soil or concrete.
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Goiania orphaned source dispersal, 1987
• The response generated large quantity of radioactive waste.
• Packaging: • 3800 metal drums,• 1400 metal boxes,• 10 shipping container,• 6 sets of concrete packaging.
• The final volume of waste was 3500 m3 (275 lorry loads).
• Temporary waste storage site was chosen 20 km from Goiania.
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18
Goiania orphaned source dispersal, 1987
Key points�The event was triggered by allowing a source to become
in a state of not being secure and under control.o Liability of regulatory authorities and the person designated as being
responsible for the radioactive source.
�Radioactive materials got into inadequate hands.
� Late recognitiono Recognition of the nature of radiation injury depends on education of health and
safety professions. This can aid speed of diagnosis and overall speed of response.
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� HASS provides a regulatory framework for the control of RS (ionising
radiation in generalzd that have the potential to cause harm if they are not
managed properly.
� The main goal of HAAS is to prevent exposure of workers and the public to
ionising radiation arising from inadequate control of high-activity sealed
radioactive sources and orphan sources and to harmonise controls in place in
the Member States by defining specific requirements ensuring that each such
source is kept under control.
EU legal framework
The HASS Directive (High-Activity Sealed Source)COUNCIL COUNCIL COUNCIL COUNCIL DIRECTIVE 2003/122/EURATOMDIRECTIVE 2003/122/EURATOMDIRECTIVE 2003/122/EURATOMDIRECTIVE 2003/122/EURATOM
of 22 December 2003 on the control of highof 22 December 2003 on the control of highof 22 December 2003 on the control of highof 22 December 2003 on the control of high----activity sealed radioactive sources and activity sealed radioactive sources and activity sealed radioactive sources and activity sealed radioactive sources and orphan sourcesorphan sourcesorphan sourcesorphan sources
Addressing safety and security of radioactive sources
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COUNCIL DIRECTIVE 2003/112/EURATOM (HASS)
� HASS’s requirements are closely linked to the IAEA Code of Conduct on the
safety and security of radioactive sources and its related guidance
� HASS was satisfactory implemented in the Member States. Report was
issue in its implementation with recommendations
� COUNCIL DIRECTIVE 2013/59/EURATOM of 5 December 2013 laying down
basic safety standards (BSS) for protection against the dangers arising
from exposure to ionising radiation
� BSS repeals five directives
including HASS
Summary
� RSs need to be safely and securely managed with options ontheir inventory, storage, disposal, import/export.
� Dissemination of best practices for the development of anational response plan for potential RN safety/securityevents.
� IAEA and several international organizations such as EC, USDoE carry out large out reach programmes to support buildSecurity and Security Regimes.
� CoC is not legally binding, however many Member Statewrote to the Director General to support IAEA efforts onsafety and security of radioactive sources. There is a strongsupport for the CoC among Member States and internationalorganisations.
� The EU legislation frame for Safety/Security aims at gettingas harmonized as possible with the International standardssuch with the CoC. 38