RADIATION PROTECTION NO 160 - European Commission

1 European Commission RADIATION PROTECTION NO 160 Technical Recommendations for monitoring Individuals Occupationally Exposed to External RADIATION Directorate-General for Energy and Transport Directorate H Nuclear Energy Unit RADIATION PROTECTION 2009 Final Report of Contract TREN/07/ Prepared by a Consortium composed of the Greek Atomic Energy Commission (GAEC) and the scientific society European RADIATION Dosimetry Group, EURADOS through a task group of experts: EURADOS Task Group members are as follows: Jo o Garcia-Alves, ITN (Portugal) Peter Ambrosi, PTB (Germany) David Bartlett (UK) Lorraine Currivan, RPII (Ireland) Janwillem van Dijk, NRG (the Netherlands) Elena Fantuzzi, ENEA (Italy) Vasiliki Kamenopoulou, GAEC (Greece) 3 FOREWORD Luxembourg, October 2009 Under the terms of the Treaty establishing the European Atomic Energy Community, the Community, amongst other things, establishes uniform safety standards to protect the health of workers and of the general public against the dangers arising from ionizing RADIATION .

2 The standards are approved by the Council, on a proposal from the Commission , established taking into account the opinion of the Group of Experts referred to in Article 31 of the Treaty. The most recent version of such standards is contained in Council Directive 96/29/Euratom of 13 May 1996 laying down basic safety standards for the PROTECTION of the health of workers and the general public against the dangers arising from ionizing RADIATION . Directive 96/29/Euratom introduces, inter alia, principles for the operational PROTECTION of workers exposed to ionising RADIATION , including requirements for the monitoring of individuals exposed to external RADIATION . The Directive and its requirements have been implemented in all Member States with variations. With the objective to harmonise the technical implementation of these requirements, the Commission provided already in 1975 guidance on individual monitoring of external RADIATION .

3 The most recent Technical recommendations for monitoring individuals occupationally exposed to external RADIATION were published by the Commission in 1994, as RP 73. The 1994 recommendations were drafted under contract and published after detailed consideration by the Article 31 Group of Experts. In 2007, the Commission decided to award a contract to update the 1994 recommendations and to prepare new draft technical recommendations for consideration by the Article 31 Group of Experts and by the Commission . The 2009 Technical Recommendations for monitoring Individuals Occupationally Exposed to External RADIATION were drafted under contract and subsequently discussed with various stakeholders. The draft document has been presented to the Article 31 Group of Experts for discussion and approval at their meeting of 9 11 June 2009.

4 The Article 31 Group of Experts endorsed the document and recommended it for publication by the Commission . Augustin Janssens Head of RADIATION PROTECTION Unit 5 CONTENTS FOREWORD .. 3 5 ABBREVIATION LIST .. 7 1 PURPOSE AND SCOPE .. 9 Purpose .. 9 Context .. 9 11 Scope .. 12 Guide to the document ..14 2 FRAMEWORK FOR INDIVIDUAL 17 17 Recommendations ..18 Terms .. 18 Framework 19 Status of individual monitoring in the 20 21 Standards .. 23 3 DOSIMETRY CONCEPTS, PROTECTION AND OPERATIONAL QUANTITIES; DETERMINATION OF THE OPERATIONAL QUANTITIES EXPOSURE .. 25 25 Recommendations ..25 Terms .. 26 Dosimetry concepts .. 27 Relationships of the PROTECTION and operational quantities .. 29 Estimation of effective dose and equivalent 31 Determination of operational quantities using personal dosemeters.

5 32 4 INDIVIDUAL monitoring PROCEDURES .. 35 35 Recommendations for a monitoring 36 Terms .. 38 Dosemeter requirements and choice of personal dosemeter .. 39 Active personal dosemeters .. 41 Use of algorithms .. 41 Characteristics of workplace fields .. 42 Individual monitoring based on workplace monitoring .. 46 5 ASSESSMENT OF UNCERTAINTIES .. 49 49 Recommendations ..50 Terms .. 51 Measurement Formulation stage of uncertainty 52 Calculation stage of uncertainty evaluation .. 53 Thresholds .. 56 How realistic is the uncertainty evaluation? .. 58 Appraisal of uncertainty evaluation .. 60 Reporting of An example .. 60 Technical Recommendations for monitoring Individuals Occupationally Exposed to External RADIATION 66 REQUIREMENTS FOR ACCURACY OF DOSE ASSESSMENTS .. 67 67 Recommendations.

6 68 Terms .. 68 Factors affecting the accuracy of a dose 69 Accuracy of a real measurement .. 70 Workplace field specific correction 71 Background subtraction .. 73 7 CALIBRATION AND TYPE 77 77 Recommendations ..77 Terms .. 78 Type testing .. 80 Software .. 81 Determination of the reference calibration factor 82 Determination of the individual normalization factor 84 Other 84 Use of personal dosemeter as area monitors .. 85 8 GENERAL CRITERIA FOR APPROVAL OF DOSIMETRY 87 87 Recommendations for requirements for 87 Terms .. 88 The approval process ..90 Performance 90 Participation in national/international 92 9 DOSE REPORTING, RECORD KEEPING AND INFORMATION SYSTEMS 93 93 Recommendations ..94 Terms .. 94 Main partners in dose record keeping and the transfer of data .. 97 Dose assessment and dose reporting.

7 101 Dose information systems .. 103 NDR links to other data sources and 104 10 RELIABILITY OF DOSE ASSESSMENT, QUALITY ASSURANCE AND QUALITY CONTROL .. 107 107 Recommendations .. 107 Terms .. 108 Implementation of a QA/QC Management 108 Managing Technical Aspects of a QMS .. 112 11 BASIS FOR PROCEDURES AND CRITERIA FOR MUTUAL RECOGNITION OF APPROVED DOSIMETRY SERVICES IN 117 117 Criteria for the harmonization of approval 118 Further considerations of harmonization of approval procedures .. 119 REFERENCES .. 121 7 ABBREVIATION LIST ADS Approved Dosimetry Service AOHS Approved Occupational Health Service AP Antero-Posterior APD Active personal dosemeter BSS Basic Safety Standards [EU 1996a, IAEA 1996] CENELEC European Committee for Electrotechnical Standardization CLT Central Limit Theorem CONRAD Coordinated Network for RADIATION Dosimetry ( ) Dair Absorbed dose in air (Gy) DG TREN European Commission Directorate General Transport and Energy ( ) DIS Direct Ion Storage dosemeter DT Absorbed dose in tissue (Gy) E Effective dose (Sv) EA European co-operation for Accreditation EC European Commission ( ) EN European Norm ( ) ESOREX European Study on Occupational RADIATION Exposure EU European Union ( ) EURADOS European RADIATION Dosimetry group ( )

8 EURADOS WG2 EURADOS Working group on Harmonization of Individual monitoring in Europe ( ) EURATOM European Atomic Energy Community ( ) EU-Trimer European Technical Recommendations for Individual monitoring of External RADIATION EVIDOS Evaluation of individual dosimetry in mixed neutron and photon RADIATION fields ( ) eV Electron volt (1 eV = 10-19 joule) GUM Guide to the expression of Uncertainty in Measurement [JCGM 100] ( ) GUMF GUM Framework Gy Gray, SI unit of dose (joule per kilogram, ) H'(d) Directional dose equivalent at a depth of d mm in tissue (Sv) H*(d) Ambient dose equivalent at a depth of d mm in tissue (Sv) Hp(d) Personal dose equivalent at a depth of d mm in tissue (Sv) HPS Health Physics Society ( ) HSE UK's Health and Safety Executive ( ) HT Tissue equivalent dose (Sv) IAEA International Atomic Energy Agency ( ) ICRP International Commission on Radiological PROTECTION ( ) ICRU International Commission on RADIATION Units and Measurements ( ) IEC International Electrotechnical Commission ( ) IMS Individual monitoring Service ISO Iso-directional ISO International Organization for Standardization ( ) ISOE Information System on Occupational Exposure ( ) JCGM Joint Committee for Guides in Metrology ( ) Technical Recommendations for monitoring Individuals Occupationally Exposed to External RADIATION 8 Kair Kerma in air (Gy) keV kilo electron volt (1 keV = 103 eV) KT Kerma in tissue (Gy) LET Linear Energy Transfer (keV/ m) LLAT Left Lateral LPU Law of Propagation of Uncertainty MCM Monte Carlo Method MeV mega electron volt (1 MeV = 106 eV)

9 NCRP National Council on RADIATION PROTECTION and Measurement ( ) NDR National Dose Register NIST National Institute of Standards and Technology ( ) NMI National Metrology Institute NPL National Physical Laboratory ( ) NSO National Standardization Organization ORAMED Optimization of RADIATION PROTECTION for MEDical staff ( ) OSL Optically Stimulated Luminescence OWD Outside Workers Directive [EU 1990] PA Postero-Anterior PDF Probability Density Function PMMA Polymethylmethacrylate PTB Physikalisch-Technische Bundesanstalt ( ) Q(L) Quality factor defined as a function of LET, L QA Quality assurance QC Quality control QMS Quality Management System RBE Radiobiological Effectiveness RLAT Right Lateral ROT Rotational RPE RADIATION PROTECTION Expert RPL Radiophotoluminescence SI International System of units or Syst me International d unit s ( ) SSDL Secondary Standard Dosimetry Laboratory SSK Strahlensch tzkommission ( ) Sv Sievert, SI unit of dose equivalent ( with the special name sievert)

10 TLD Thermoluminescence Dosemeter UNSCEAR United Nations Scientific Committee on the Effects of Atomic RADIATION ( ) VIM International Vocabulary of Basic and General Terms in Metrology [JCGM 200] ( ) WELMEC European Cooperation in Legal Metrology ( ) wR RADIATION weighting factor wT Tissue weighting factor PURPOSE AND SCOPE 9 1 PURPOSE AND SCOPE Purpose The purpose of the European Commission Technical Recommendations for monitoring Individuals Occupationally Exposed to RADIATION is to provide guidance on those aspects of the implementation of the European Union (EU) Parliament and Council Directives that are directly related to individual monitoring of external RADIATION , and to encourage harmonization thereof. The Technical Recommendations are primarily aimed at the management and staff of European individual monitoring services.