Expert Advisory Group Meeting EAGM on Intercomparison for Assessment of Occupational Exposure 14 to

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Expert Advisory Group Meeting (EAGM) on
Intercomparison for Assessment of Occupational
Exposure14 to 18 February 2005Tokai, Japan

• Michio YOSHIZAWA1 and Toshikazu SUZUKI2
• 1 Japan Atomic Energy Research Institute (JAERI)
• 2 National Institute of Radiological Sciences
  (NIRS)

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Overview

• Purpose Determine the future direction and
  programme of the intercomparison, including the
  discussion of the necessity of expanding
  intercomparison into internal monitoring, neutron
  dosimetry and workplace monitoring.
• Period 14 to 18 February 2005
• Place Japan Atomic Energy Institute, JAERI and
  Japan Nuclear Cycle Development Institute, JNC

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Participants

• External dosimetry
• Dr. Neil MORRIS,(Australia, ARPANSA)
• Dr. Bong-Hwan KIM(Korea, KAERI)
• Mr. Hideaki YAMAMOTO(Japan, JAERI)
• Mr. Michio YOSHIZAWA (Japan, JAERI)
• Mr. Norio TSUJIMURA(Japan, JNC)

• Internal dosimetry
• Dr. A.G. Hegde,(India, BARC)
• Mr. Toshikazu SUZUKI(Japan, NIRS)
• Mr. Takumaro MOMOSE(Japan, JNC)
• Mr. Osamu KURIHAERA (Japan, JNC)

IAEA Technical Officer Mr. Rodolfo CRUZ SUÁREZ
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Contents

• Review of previous activitiesA. External
• RCA Personal Dosimetry Intercomparison
• Phase 1 (90-92), Phase 2(95-96), Phase
  3(01-04)
• WS on Neutron Monitoring and Dosimetry (Korea,
  2001)
• IAEA Intercomparisons g, gn
• B. Internal
• TC on Assessment of Occupational Exposure Due to
  Intakes of Radionuclides (India, 2004)
• IAEA Intercomparison
• Discussion and Report making
• Current situation, Future direction, Needs,
  Proposed activities, Timetable, etc.

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Content of the EAGM Report

• Introduction
• Background technical information
• Assessment of occupational exposure from external
  radiation sources
• Current situation
• Identified needs
• Proposed activities
• Expected results
• Assessment of occupational exposure due to
  intakes of radionuclides
• Current situation
• Identified needs
• Proposed activities
• Expected results
• Timetable of activities and budget for 2005-2008
• Conclusion and recommendations
• Annexes List of participants, Agenda of the
  meeting

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Introduction and BG technical Info.

• Introduction
• Purpose of the meeting
• Background technical information
• Summary Tables on
• Availability of services providers for external
  and internal dosimetry,
• Status of implementation of IAEA requirement for
  individual and workplace monitoring of each
  Member States, and the number of Radiation
  workers.
• Total number of radiation workers in the RCA MS
  gt840,000

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Current situation External (1)

• for photons and beta
• Participated MS in Personal Dosimetry
  Intercomparison
• Phase 1 (90-92) 17 labs. from 14 MS
• Phase 2 (95-96) 38 labs. from 16 MS
• Phase 3 (01-05) 25 labs. from 16 MS
• The Intercomparison exercise has clearly improved
  the performance of dosimetry services.
• Individual monitoring for most participating
  laboratories is now at an acceptable level.
• Evaluation of the ability of calibration of
  workplace monitoring equipment and personal
  monitoring for low penetrating radiations and for
  extremities have not yet undertaken.

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Improvement by the intercomparison
Cs-137
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Improvement by the intercomparison (2)
X-ray (110kV-wide)
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Current situation External (2)

• for neutrons
• Participated Member States
• WS for Neutron Monitoring and Dosimetry (2001,
  KAERI) 7
• IAEA mixed (n-g) fields Intercomparison
  (20032005) 7
• Total 10
• Approximately 10 of radiation workers seems to
  be exposed to neutron in workplace.
• Most participated MS have a problem with the
  calibration of neutron monitoring devices.
• There is a big gap in the level of neutron
  dosimetry techniques between participated MS.
• Information on neutron exposure, such as
  practices, sources, monitoring program, etc. is
  insufficient.
• Neutron sources other than nuclear facilities
  might exist. ex. high energy (gt67MeV) LINAC for
  radiation therapy

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Proposed activities External (1)

• Questionnaire (2005)- to obtain updated
  information on workplace and beta/extremities
  monitoring, neutron sources and the number of
  radiation workers exposed to neutron, etc.
• Intercomparison of Area Monitoring Instruments
  for photons and beta radiations (in a Workshop,
  2006) - to establish reliability of workplace
  monitoring for photons and beta radiations.
• Calibration of neutron area-survey meters
  (2006)- to provide a reliable calibration
  factors, and- to produce in-site calibration
  factor for neutron personal dosemeters.

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Content of the EAGM Report

• Introduction
• Background technical information
• Assessment of occupational exposure from external
  radiation sources
• Current situation
• Identified needs
• Proposed activities
• Expected results
• Assessment of occupational exposure due to
  intakes of radionuclides
• Current situation
• Identified needs
• Proposed activities
• Expected results
• Timetable of activities and budget for 2005-2008
• Conclusion and recommendations
• Annexes List of participants, Agenda of the
  meeting

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Proposed activities External (2)

• TC to respond to the identified needs of neutron
  monitoring and dosimetry (2007)- to disseminate
  basic knowledge and techniques for neutron
  monitoring in workplace.
• Discussion on Memorandum of Understanding- for
  providing Member States dosimetry services access
  to well-equipped neutron calibration facilities.
• Three Yearly Performance Testing Program (2007-
  to support the Quality Management and
  Accreditation, and simultaneously Phase 4
  Personal Dosemeter Intercomparison (2007- for
  specific situations such as low penetrating
  radiations, extremities, angular dependence and
  high dose investigations.

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Expected results External

• Harmonization of the dosimetry and assessment of
  occupational exposure in the region.
• Detailed updated information can be obtained on
  the current situation in the Member States of
  external dosimetry for neutron and
  beta/extremities and of workplace monitoring.
• Upgrading of the neutron dosimetry in the
  workplace and for individuals.
• Reliability of workplace monitoring and personal
  monitoring.
• Exchange of experience about external dosimetry,
  including calibration techniques and performance
  testing.

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Current situation Internal

• Internal monitoring service are available in 12
  Member States.
• Dose assess are applied to a part of radiation
  workers.
• Training course of Assessment of Occupational
  Exposure due to Intake of Radionuclides was held
  in BARC/India (2003).
• Intercomparison exercise of direct measurement of
  radionuclides in simulated human organ was
  implemented.
• IAEA/IDEAS intercomparison for internal dose
  calculation has been putting into practice.

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Proposed activities Internal (1)

• Compilation of the result of the IAEA exercise
  and in-vivo monitoring using the phantoms
  (2005)- to verify the methodologies of internal
  dose assessment and take corrective action.
• Intercomparison exercises using air filter
  samples of a single gamma emitter and multiple
  radionuclides of alpha and beta emitters (2006)-
  to improve air contamination assessment
  technology.
• Intercomparison exercises using spiked urine
  samples of alpha, beta and gamma emitters
  (2006)- to improve measurement and analysis
  technology.

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Proposed activities Internal (2)

• TC for usage of most appropriate software for
  internal dose estimation among the Member States
  (2007) - to harmonize the dose calculation
  methodology.
• Periodical Intercomparison of the in vivo
  counters among the regional Member States using
  BOMAB and Thyroid phantom as a part of quality
  control/quality assurance (2008) - to support
  the Quality Management and Accreditation

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Expected results Internal (1)

• Improvement of calibration methods for direct and
  indirect monitoring system with the use of
  phantoms and spiked samples.
• Evaluation and documentation of the possibility
  for improvement of radiochemical methods and
  measurement techniques for alpha-beta emitters.
• Improvement and regional harmonization of dose
  calculation methodology thorough implementation
  of recent ICRP models and IAEA Safety documents.
• Delineation of requirements for PC based software
  for internal dose assessment. Survey available
  software packages in order to recommend suitable
  programs for regional use.

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Expected results Internal (2)

• Harmonization of analysis, performance
  requirement and performance test procedure for
  direct measurement methods, indirect measurement
  methods and air monitoring systems.
• Establishment of appropriate Quality Assurance
  Systems for internal dosimetry services.

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Conclusions

• The Expert Advisory Group Meeting held in Tokai,
  Japan with the participation of experts from
  Australia, India, Japan, Korea, and IAEA expert.
• The experts discussed the achievements of the
  activities carried out by RAS/9/029 and the
  future direction and programme of the
  intercomparison, including the discussion of the
  necessity of expanding intercomparison into
  internal monitoring, neutron dosimetry and
  workplace monitoring.
• The EAGM prepared a comprehensive summary of the
  current situation in the region for the
  monitoring techniques discussed and proposed a
  set of activities to be carried out in external
  and internal fields.