Introduction to
Incorporation Monitoring
When handling open radioactive substances and due to radioactive accidents or contaminations but also neutron activations it may occur that radionuclides are incorporated into the body, e.g. by inhalation, ingestion, through the skin or through an open wound.
This leads to internal radiation exposure.
It is the task of incorporation monitoring to assess the internal doses retrospectively whether for workers or people of public.
The body dose can be composed of internal and external radiation exposure, depending on conta-mination or working conditions, the path of intake, the chemical form of the substances and the type of radionuclides.
Methodes of Responsibility
The monitoring of incorporations are regulated in the National Guideline of Physical Radiation Protection Control. The following monitoring methods for the
determination of the incorporated activities are
It is our (ISuS) challenge to offer only systems with outstanding detection limits (LLD)
commonly used:
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In-vivo methods: Direct determination of activities in the body and the organs.
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In-vitro methods: Determination of activity concentration in excretions.
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Room air measurements: Determination of activity concentration in the air at work-places (labs) or habitats.
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Contamination measurements on the body and at workplaces (labs) or habitats.
Retrospective Assessment
It is the task of incorporation monitoring to assess doses retrospectively. In general, if people of public or workers are occupationally exposed by handling open radioactive sources or after a nuclear event, incorporation monitoring is necessary. The incorpo-rated activities are determined and the body dose resulting from this uptake is assessed using the monitoring data.
Determining of body and organ activities using in-vivo counters is of enormous presence to
protect workers but also the population
after radioactive releases.
Techniques of Investigation
In-vivo monitors
Incorporation monitors (In-vivo counters) are designed to protect workers and people of public in the field of medical therapy and diagnostic, fertilizer and oil industry, waste and military applications, NPP’s, industry, universities, national and research institutes as well as miners and further fields of applications.
Types of in-vivo monitoring geometries we realised:
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Whole an Partial body counters WBC, PBC
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Fix and variable detector positions
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Scanning bed and scanning detector technologies
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Organ counters:
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Lung & Liver counter LC,
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Stomach counter SC,
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Bone counter BC: head, knee and back
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Special counters:
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Thyroid counter TC and scanner TS
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Beta/Gamma counter BGC
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Individual research counter IRC
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Types of shielding geometries we realised:
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Heavy labyrinth version for basement (variable geometries, lowest LLD)
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Heavy chamber version for basement (fix geometry, lowest LLD)
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Standard room version with light shadow shields inside (open space, medium LLD)
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Mobile chamber version with light shadow shields inside (driveable, medium LLD)
Types of detector we used:
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HPGe-, Si(Li)-, Cd(Tl)-, NaI-, BGO-, Scintillation- & Proportional Detectors
Important radionuclides to be measured:
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All measurable radionuclides from: natural primordial/cosmogenic & anthropogenics
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Incorporations from medical therapy and diagnostic, fertilizer and oil industry, waste and military applications as well as phosphate and other mines.
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Natural radionuclides are: U-238, Th-232, U-235 with their daughters as well as Ra-226, 228, 225 and their daughters like Pb-210 but also K-40, Cs-137 and additional nuclides of interest like actinides such as Pu-isotopes.
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Energy range: 20 keV up to 3 MeV
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It covers also fission and activation products, e.g from full-outs and workplace contaminations as well as Pu isotopes in the lung.
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Some radionuclides as K-40, Cs-137, Th-isotopes are homogeneously distributed in the body tissue and muscles.
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U-, Ra- and Sr-isotopes but also Pb-210 are deposited mostly in the bones if ingestion is the primary path of intake and in the lung if inhalation is the primary way of intake.
State of the art technology
Install state-of-the-art incorporation monitoring technologies
to measure γ-rays with high resolution HPGe and/or NaI detectors in labyrinth, fully or shaddow shielded lead spaces/chambers for all measuring geometries (whole & partly body as well organs) on the human body.
Applicable for homogeneous and inhomogeneous distributed radionuclides in the human body emits γ- and β-rays as well as Bremsstrahlung.
Below are some examples for in-vivo monitors:
Partial Body Counter
University Medical Center Graz
Shadow shielded HPGe/BGO partial body counter to measuring children and adults under supervision of nurse and/or mother in a standard room
Whole Body Counter
BfS Munich Germany
Labyrinth shielded measuring chamber using 4 HPGe & NaI detectors in bed geometry to measure the total body radioactivity (picture with IGOR calibration phantom).
Whole Body Counter
Seibersdorf Laboratories Austria
Partially shielded measuring room using 2 shielded HPGe detectors in scanning bed geometry to measure the total body radioactivity (picture with bottles calibration phantom).
Lung counter
KWU Germany
Fully shielded compact measuring chamber using four HPGe detectors for medium-energies to measure occupational people working with open radioactive materials
Scanning whole body counter
PNNL USA
Fully shielded measuring chamber using 3 HPGe detectors in scan bed geometry to measure the total body radioactivity distribution
Sr-90/Cs-137 counter
BfS Munich Germany
Special mobile incorporation monitor using a shaddow shield design for beta and photon head measurements and for simultaneously photon stomach measurements.