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The TECHREC project, funded by the European Commission, will provide Technical Recommendations for Monitoring Individuals for Occupational Intakes of Radionuclides. It is expected that the document will be published by the European Commission as a report in its Radiation Protection Series during 2016. The project is coordinated by the European Radiation Dosimetry Group (EURADOS) and is being carried out by members of EURADOS Working Group 7 (Internal Dosimetry). This paper describes the aims and purpose of the Technical Recommendations, and explains how the project is organised.
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TECHNICAL RECOMMENDATIONS FOR MONITORING
INDIVIDUALS FOR OCCUPATIONAL INTAKES OF
RADIONUCLIDES
G. Etherington1,*, P. Be
´rard2, E. Blanchardon3, B. Breustedt4, C. M. Castellani5, C. Challeton-de Vathaire3,
A. Giussani6, D. Franck3, M. A. Lopez7, J. W. Marsh1and D. Nosske6
1
Public Health England (PHE), Centre for Radiation Chemical and Environmental Hazards, Didcot, UK
2
Commissariat a
`l’E
´nergie Atomique et aux E
´nergies Alternatives (CEA), France
3
Institut de Radioprotection et de Su
ˆrete
´Nucle
´aire (IRSN), France
4
Karlsruhe Institute of Technology (KIT), Germany
5
Agenzia nazionale per le nuove tecnologie, l’energia e lo sviluppo economico sostenibile (ENEA), Italy
6
Bundesamt fu
¨r Strahlenschutz (BfS), Germany
7
Centro de Investigaciones Energe
´ticas, Medioambientales y Tecnolo
´gicas (CIEMAT), Spain
*Corresponding author: george.etherington@phe.gov.uk
The TECHREC project, funded by the European Commission, will provide Technical Recommendations for Monitoring
Individuals for Occupational Intakes of Radionuclides. It is expected that the document will be published by the European
Commission as a report in its Radiation Protection Series during 2016. The project is coordinated by the European Radiation
Dosimetry Group (EURADOS) and is being carried out by members of EURADOS Working Group 7 (Internal Dosimetry).
This paper describes the aims and purpose of the Technical Recommendations, and explains how the project is organised.
INTRODUCTION
A number of international organisations provide stan-
dards, guidance, advice, and scientific and technical in-
formation on topics related to monitoring individuals
for occupational intakes of radionuclides. However, no
single document presents a complete account of the
subject. The International Commission on Radiological
Protection (ICRP) provides biokinetic and dosimetric
models and data intended for the assessment of internal
doses resulting from radionuclide intakes, in a series of
publications
(1–10)
. While these models and data are es-
sential tools for assessing internal doses, ICRP does not
provide comprehensive guidance or recommendations
on internal contamination monitoring, neither does it
provide practical guidance on the methods for assessing
internal doses from individual monitoring data, except
in the case of simple situations where the worker is
exposed to a single radionuclide, and a single measure-
ment is made using a single monitoring method.
Working Group 13 of ISO Technical Committee
85, Sub-Committee 2 (TC85/SC2) has provided inter-
national standards on monitoring and internal dose
assessment
(11 – 13)
, which provide a highly standar-
dised approach that is appropriate for a significant
fraction of cases where monitoring and internal dose
assessment is required in the event of occupational
intakes of radionuclides. However, the approach
is not appropriate for complex cases where multiple
measurements have been made using different moni-
toring methods.
IAEA and ICRU have also provided guidance on
specific topics
(14 – 17)
, while EURADOS has issued
guidelines on the specific issue of a structured ap-
proach to internal dose assessment
(18)
.
The TECHREC project aims to meet the need for a
comprehensive, unified account of the subject by provid-
ing a report that will present Technical Recommendations
for Monitoring Individuals for Occupational Intakes of
Radionuclides. It is expected that the report will be pub-
lished by the European Commission in its Radiation
Protection Series during 2016. It will be complementary
to an already-published report that presents technical
recommendations for monitoring individuals occupa-
tionally exposed to external radiation
(19)
. The project is
coordinated by the European Radiation Dosimetry
Group (EURADOS) and is being carried out by
members of EURADOS Working Group 7 (Internal
Dosimetry). It commenced in May 2014 and will be
completed in May 2016.
The report will describe the principles of the
subject, and provide a comprehensive Best Practice
Guide. The Technical Recommendations will take
account of all recent developments and will be fully
up-to-date. They will also take account of future
developments, such as the expected updates to the EU
2013 Basic Safety Standards (EU-BSS) that will take
account of developments embodied in the ICRP
Occupational Intakes of Radionuclides (OIR) report
series
(20)
. It is expected that the OIR report series (and,
by implication the Publication 103 dosimetry system),
#Crown copyright 2015.
Radiation Protection Dosimetry (2016), Vol. 170, No.14, pp. 812 doi:10.1093/rpd/ncv395
Advance Access publication 13 October 2015
will effectively be adopted for internal dosimetry
by national authorities in EU countries on or before
February 2018. The Technical Recommendations have
therefore been developed so that they will be equally
applicable both before and after adoption of the OIR
report series by national authorities.
The Technical Recommendations are intended to be
primarily informative in nature, providing guidance
and recommendations on best practice. They will not in
themselves make prescriptive or normative statements
about practices that must be adopted. Nevertheless,
the Technical Recommendations will make clear where
authorities or organisations (e.g. the EU EURATOM
Directive, ISO or ICRP) have specified that certain
methods, practices or conventions are mandatory
according to their own regulations or schemes.
The target audience includes internal dosimetry
services operating within the EU, as well as compe-
tent national and international authorities. The
Technical Recommendations are also expected to be
of interest to site operators who are responsible for ra-
diation protection programmes, radiation protection
experts who provide advice to site operators, manu-
facturers, laboratories providing bioassay services,
and government bodies aiming to harmonise regula-
tions and guidance.
ORGANISATION OF THE PROJECT
The project is organised according to the work
package (WP) structure shown in Figure 1. The figure
also shows the main interactions among the WPs. WP1
developed a methodology for drafting the Technical
Recommendations, including specification of the source
documents to be taken into account, and quality assur-
ance criteria.
The most important source documents are sum-
marised in Figure 2. Some of these source documents
are currently under revision, as indicated by the
shaded boxes in the figure.
The contents of such source documents will not be
reproduced in detail, since this would result in a
report of excessive (and unnecessary) length. Rather,
the information that can be found in these documents
will be summarised, and guidance will be given on
how to make best use of this information.
An important feature of the project is the strong
emphasis placed on national and international con-
sultations (WP2), both with colleagues working in in-
ternal dosimetry and with stakeholders.
For the first consultation, selected members of
EURADOSWorkingGroup7wereinvitedtoprovide
comments during January and February 2015. For the
Figure 1. TECHREC work package structure.
MONITORING OCCUPATIONAL INTAKES OF RADIONUCLIDES
9
second (external stakeholder) stage of consultation, na-
tional contacts (one per country) were identified in the 28
EU countries, 5 non-EU European countries (Albania,
Norway, Russia, Switzerland and Ukraine), 6 countries
in Asia and America (Argentina, Brazil, Canada,
China, Japan and United States) and 7 international
organisations (ICRP, IAEA, ISO, PROCORAD, the
EURATOM Article 31 Expert Group and ILO). The na-
tional contacts were asked to identify stakeholders, and a
total of 32 national contacts provided answers. These
national contacts were from 22 EU countries (Belgium,
Bulgaria, Croatia, Czech Republic, Denmark, Finland,
France, Germany, Greece, Hungary, Italy, Ireland,
Lithuania, Malta, Poland, Portugal, Romania, Slovakia,
Slovenia, Spain, Sweden and UK), 4 non-EU European
countries and 6 non-European countries.
A list of external stakeholders at national level was
then generated, which included Internal Dosimetry
Services, Radiation Protection Services, Regulatory
Bodies and National Radiation Protection Associations.
This final List of Stakeholders contains 227 persons from
32 countries, and 8 ‘reference organisations’ and expert
groups (which includes a High Level Group of Qualified
Experts on internal dosimetry and radon monitoring).
The external stakeholder consultation took place
during March and April 2015. A complete ‘First
Draft’ was then produced in May 2015, taking into
account the comments received, and sent to the
European Commission for comment.
CONTENT OF THE TECHNICAL
RECOMMENDATIONS
Topics addressed in the Technical Recommendations
(WP3) are summarised in Table 1.
As well as the topics that would be expected in
such a document (i.e. General Principles, Monitoring
Techniques, Monitoring Programmes, Routine and
Special Dose Assessment, Quality Assurance, Require-
ments for Internal Dosimetry Services), a number of
specialist topics are also addressed. These include:
monitoring and dosimetry for wound cases, monitor-
ing and dose assessment when decorporation therapy
treatment has been applied, dosimetry for intakes of
radon and its progeny, monitoring for first responders
in the event of a major accident at a nuclear facility,
and dosimetry for the specific application of assess-
ment of risks to health (rather than for radiation pro-
tection purposes).
NEXT STEPS
The Recommendations will be developed further
during 2015, and a final stage of external stakeholder
consultation will be initiated in November 2015.
Figure 2. Source documents used in the development of the recommendations.
G. ETHERINGTON ET AL.
10
During the later phases of the project, an advanced
draft will be provided to the Article 31 Group of
Experts for their review and comment (WP4).
The final version of the Technical Recommendations
in publishable form will be submitted to the European
Commission in May 2016.
FUNDING
The TECHREC project is funded by the European
Commission (Directorate-General for Energy, DG
ENER), under Service Contract No. ENER/2014/
NUCL/SI2.680087.
REFERENCES
1. International Commission on Radiological Protection
(ICRP). Limits for intake of radionuclides by workers.
ICRP Publication 30, Parts 1–4 and Supplements. Ann.
ICRP. Pergamon Press (1979–1988).
2. Age-dependent doses to members of the public from
intake of radionuclides. ICRP Publication 56, Part
1. Ann. ICRP 20(2). Pergamon Press (1989).
3. Human respiratory tract model for radiological protec-
tion. ICRP Publication 66. Ann. ICRP 24(1– 3).
Pergamon Press (1994).
4. Age-dependent doses to members of the public from
intake of radionuclides: Part 2, Ingestion dose coeffi-
cients. ICRP Publication 67. Ann. ICRP 23(3/4).
Pergamon Press (1993).
5. Dose coefficients for intake of radionuclides by workers.
ICRP Publication 68. Ann. ICRP 24(4). Pergamon
Press (1994).
6. Age-dependent doses to members of the public from intake
of radionuclides: Part 3, Ingestion dose coefficients.ICRP
Publication 69. Ann. ICRP 25(1). Pergamon Press (1995).
7. Age-dependent doses to members of the public from intake
of radionuclides: Part 4, Inhalation dose coefficients.
ICRP Publication 71. Ann. ICRP 25(3/4). Pergamon
Press (1995).
8. Age-dependent doses to members of the public from
intake of radionuclides: Part 5 Compilation of ingestion
and inhalation dose coefficients. ICRP Publication 72.
Ann. ICRP 26(1). Pergamon Press (1996).
9. Individual monitoring for internal exposure of workers –
Replacement of ICRP Publication 54. ICRP Publication
78. Ann. ICRP 27 (3/4). Pergamon Press (1997).
Table 1. Chapter headings and topics addressed in the technical recommendations.
Chapter Topics
A. Purpose, context, scope and overview Purpose, context and scope of the technical recommendations
Overview of internal dosimetry and monitoring
B. General principles Dosimetric and operational quantities
Biokinetic and dosimetric models
Methodologies for the assessment of intakes of radionuclides:
fundamental aspects including bioassay functions
Dose assessment: basic principles (including dose coefficients)
C. Monitoring techniques Methods of individual and workplace monitoring
D. Monitoring programmes Design of individual monitoring programmes
E. Routine and special dose assessment Interpretation of monitoring data
Dose assessment and interpretation: in practice—routine
monitoring
Dose assessment and interpretation: in practice—special
monitoring
Monitoring and dosimetry for wound cases (and cutaneous
contamination)
Monitoring and dose assessment in the event of ‘decorporation
therapy’
F. Uncertainties Accuracy requirements and uncertainty analysis
G. QA and criteria for approval and accreditation Dose recording and reporting
Quality assurance and quality control—monitoring
Quality assurance and quality control—dose assessment
Accreditation/certification according to ISO/IEC standards
and training
Participation in national and international intercomparisons
H. Requirements for internal dosimetry services Requirements for internal dosimetry services
Annex I. Reference biokinetic and dosimetric models
Annex II. Example dose calculations
Annex III. Radon dosimetry for workers
Annex IV. Monitoring and internal dosimetry for first
responders in a major accident at a nuclear facility
Annex V. Internal dosimetry for assessment of risks to
health (e.g. compensation cases)
MONITORING OCCUPATIONAL INTAKES OF RADIONUCLIDES
11
10. Human alimentary tract model for radiological protection.
ICRP Publication 100. Ann. ICRP 36(1–2). Elsevier
(2006).
11. Radiation protection. Monitoring of workers occupation-
ally exposed to a risk of internal contamination with
radioactive material. ISO 20553:2006. ISO (2006).
12. Radiation Protection. Dose assessment for the monitor-
ing of workers for internal radiation exposure. ISO
27048:2011. ISO (2011).
13. Radiation Protection. Performance criteria for radio-
bioassay. ISO 28218:2010. ISO (2011).
14. IAEA Safety Guide. Assessment of occupation exposure
due to intakes of radionuclides. IAEA Safety Standard
Series No. RS-G-1.2. IAEA (1999).
15. Direct Methods for Measuring Radionuclides in the
Human Body, Safety Series No. 114. IAEA (1996).
16. Indirect Methods for Assessing Intakes of Radionuclides
Causing Occupational Exposure Safety Reports Series
18. IAEA (2000).
17. International Commission of Radiation Units and
Measurements. Direct determination of the body
content of radionuclides. ICRU Report 69, J. ICRU 3
(1) (2003).
18. Castellani, C. M., Marsh, J. W., Hurtgen, C.,
Blanchardon, E., Be
´rard, P., Giussani, A. and Lopez,
M. A. IDEAS Guidelines (Version 2) for the Estimation
of Committed Doses from Incorporation Monitoring
Data. EURADOS Report 2013-01 ISBN 978-3-943701-
03-6 (2013).
19. Technical Recommendations for Monitoring Individuals
Occupationally Exposed to External Radiation. Radiation
Protection RP160. Directorate-General for Energy and
Transport, Directorate H—Nuclear Energy, Unit H.4—
Radiation Protection.http:// ec.europa.eu/energy/sites/
ener/files/documents/160.pdf (last accessed 28 April
2015).
20. Occupational Intakes of Radionuclides, Parts 1 –5. ICRP
(in press).
G. ETHERINGTON ET AL.
12
... However, new methods or deviations from standard procedures that show an increased risk of significant committed dose are best accompanied by a monitoring programme [4]. There are various reference works for the dosimetry and interpretation of monitoring data, e.g. the IDEAS guidelines from EURADOS [5], ICRP-78 [6], IAEA RS-37 [7], ISO standards [8,9] or the technical recommendations from the EU [10]. For one single procedure step, the potential committed effective dose D from the intake of radionuclides can be estimated from the handled activity (A), the assumed intake fraction (or intake factor) a and the dose conversion coefficient (effective dose coefficient) e that converts the activity of internal emitters into committed effective dose (depending on the intake path and physical characteristics of the radioactive material): ...
... showed that an intake factor of 10 −7 can be assumed for standard diagnostic procedures in nuclear medicine [13]. It has also been shown that the use of a cabinet reduces the intake factor by one order of magnitude, and the use of glove boxes can reduce the intake factor by two orders of magnitude (protection safety factor f ps , see [8] and [10]). The assumption of an intake factor of 10 −4 and an effective dose coefficient of 5.7 µSv/Bq [14] for 223 Ra implies that the single handling of 1.75 MBq (resulting in an assumed intake of 175 Bq) would already lead to a potential committed effective dose of around 1 mSv. ...
... The data are taken from the electronic Annex accompaying the ICRP Occupational Intake of Radionuclides publications series [18]. An AMAD of 5 µm represents the standard assumption for the establishment of monitoring programs [4,6,7,9,10]. ...
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... Three basic principles can be applied to perform the ALARA principle. These principles can be listed as the shortest exposure time, the longest distance from the source and the optimum shielding material thickness [3,4]. Among the mentioned principles of ALARA, the term of shielding is the suitable protective barrier between the radiation source and the staff. ...
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Besides ongoing developments in the dosimetry of incorporated radionuclides, there are various efforts to improve the monitoring of workers for potential or real intakes of radionuclides. The disillusioning experience with numerous intercomparison projects identified substantial differences between national regulations, concepts, applied programmes and methods, and dose assessment procedures. Measured activities were not directly comparable because of significant differences between measuring frequencies and methods, but also results of case studies for dose assessments revealed differences of orders of magnitude. Besides the general common interest in reliable monitoring results, at least the cross-border activities of workers (e.g. nuclear power plant services) require consistent approaches and comparable results. The International Standardization Organization therefore initiated projects to standardise programmes for the monitoring of workers, the requirements for measuring laboratories and the processes for the quantitative evaluation of monitoring results in terms of internal assessed doses. The strength of the concepts applied by the international working group consists in a unified approach defining the requirements, databases and processes. This paper is intended to give a short introduction into the standardization project followed by a more detailed description of the dose assessment standard, which will be published in the very near future.
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Basic differences in the methods used in ICRP Publications 2 and 30 to derive limits for the intakes of radionuclides by workers are discussed. Although the philosophy on dose limitation now adopted by the Commission has changed, this has resulted in only small changes in the limits on intake of radioactive materials. Much greater changes result from improved knowledge about radioactive decay schemes and the uptake and retention of radionuclides in body tissues. The limits on intake recommended in ICRP Publication 30, Part l, are about equally divided above or below the corresponding values given in ICRP Publication 2 and the geometric mean of all the ratios new/old is very close to unity, although in a few instances the values differ by an order of magnitude or more. (C)1981Health Physics Society