Descriere

ABSTRACT:
Studies concerning research on dosimetry systems for use in determining materials radiation effects at facilities with high intensity radiation fields are in development.
Technical Design Report for radiation protection and safety at ELI-NP includes assessments of the facility’s radiological installations and experimental areas, as well the location and nature of detectors/instruments that should be appropriate to cover the three main areas of dosimetry for ELI-NP: personnel dosimetry, area dosimetry and environment dosimetry.
At ELI-NP facility, the basic choice for personnel dosimetry is a combination of passive gamma (Optically Stimulated Luminescence -OSL- detector) and neutron dosimeters (CR-39 - Solid-State Nuclear Track detector).
Some of the challenges addressed in the past years include the characterization of OSL for medical dosimetry and space applications, the development of neutron-sensitive OSL dosimeters, and using OSL dosimeters in case of a mass-casualty accident. All of these applications are still in the development stages and challenges and unexplored opportunities remain.
In this project, the determination of the personal dosimetry system behavior (with combination proposed above) that is a relevant study for the accurate evaluation of risks and the establishment of all radiological safety measures at ELI-NP is proposed.

DURATION:
36 months (2016-2019)

OBJECTIVES:
1. Optically Stimulated Luminescence (OSL)
2. Solid-State Nuclear Track Detection (SSNTD) or CR-39 plastic

The concrete objectives of the project are:
• The establishment of technical requirements for the characterization and the use of personal passive dosimeters from ELI-NP using OSL and SSNTD methods;
• The purchasing of international standards;
• Tests in order to characterize passive dosimetry systems in compliance with the national and international norms and regulatory requirements;
• The accomplishment of an Quality Assurance Management Plan for personal monitoring programs;
• To obtain the designation of Dosimetry Laboratory from ELI-NP as notified dosimetry laboratory by the National Commission for Nuclear Activities Control (CNCAN).

STAGES:

  • I. The establishing of the technical requirements for the using and characterization of passive dosimetry systems from ELI-NP which use the OSL and SSNTD methods and the purchase of the reference standards
    • I.1. The purchase of the international reference standards
    I.2. The establishment of the technical requirements for dosimetry systems
  • II. Testings in order to characterize the passive dosimetry systems
    • II.1. Testings for OSL dosimettry system according to the national rules and international standards
    II.2. Testings for SSTND dosimettry system according to the national rules and international standards
  • III. The develop of quality assurance program on the monitoring program
    • III.1. The develop of Quality Manual
    III.2. The establishing of the procedures and work instructions, other papers specific to the quality system implemented system
  • IV. The notification of Dosimetry Laboratory inside of ELI-NP by CNCAN
    • IV.1. The authorization of dosimetry systems at CNCAN and the notification of the dosimetry laboratory inside of ELI-NP

OBTAINED RESULTS:

    In 2016 year, it was purchased from The Romanian Standards Association (ASRO) the international standard SR EN ISO/IEC 17025:2005 - General requirements for the competence of testing and calibration laboratories, romanian version and Erata SR EN ISO/CEI 17025:2005/AC:2007, necessary to obtain the Dosimetry Laboratory designation from the National Commission for Nuclear Activities Control (CNCAN).

    Also for method validation and to characterize the dosimetry systems it was necessary to purchase the following standards:

    • for OSL for personal monitoring of photon and beta radiation
    - IEC 62387:2012 - Radiation protection instrumentation - Passive integrating dosimetry systems for personal and environmental monitoring of photon and beta radiation
    - SR EN 62387-1:2012 ver.eng. - Radiation protection instrumentation - Passive integrating dosimetry systems for environmental and personal monitoring - Part 1: General characteristics and performance requirements

    • SSNTD for personal monitoring of neutrons
    - ISO 21909-1:2015 - Passive neutron dosimetry systems - Part 1: Performance and test requirements for personal dosimetry
    - ISO 8529-3:1998 - Reference neutron radiations - Part 3: Calibration of area and personal dosimeters and determination of response as a function of energy and angle of incidence

    The totality of technical and quality assurance requirements required for dosimetry systems in order to designate the laboratory by CNCAN as the notified body dosimetry include the following steps:
    A. Studies in order to elaborate the Quality Management System (QMC) documents
    B. QMS documents elaboration based on performed studies
    C. QMS implementation
    D. Designation by CNCAN as a dosimetry laboratory

    In 2017, type tests was established according the national an international standards for passive dosimetry systems for personnel monitoring (OSL and CR39) and factors including contributions from the measurement traceability.
    The necessary tests for the characterization of passive dosimetry systems sensitive to photon/beta radiation (OSL dosimeter) and neutrons (CR39 dosimeter) must match the requirements of the international standards above mentioned for each type of dosimeter.
    In basically the performance tests are divided into two main categories:
    a) Performance tests in order to characterize intrinsic properties of the dosimetry system shall be carried out for reference energy.
    b) Performance tests to aimed to assess the effect of the influence factors (temperature, humidity, etc.).
    A. All the necessary tests for the dosimetry system which is intended to measure both photon and beta radiations (OSL) are in accord to SR EN 62387-1:2012. This European Standard applies to all kinds of passive dosimetry systems that are used for measuring the personal dose equivalent H_p (10) (for whole body dosimetry), the personal dose equivalent H_p (0,07) (for both whole body and extremity dosimetry) and the ambient dose equivalent H^* (10) (for environmental dosimetry).
    B. For dosimeter sensitive to neutron radiation, the general requirements that apply to the tests for dosimetry systems the type tests are made in accord to ISO 21909-1 and ISO 8529-3 to assess the basic characteristics of the dosimetry systems and are often ensured by recognized accredited laboratories.


CONTACT:
Dr. Dorina ARANGHEL (daranghe@ nipne.ro)
Dr. Ana STOCHIOIU (stoc@nipne.ro)
CS II. Sorin BERCEA (bercea@nipne.ro)

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PERSONAL:
Dorina ARANGHEL, Director of project, physicist
Sorin BERCEA, physicist
Elena ILIESCU, physicist engineer
Chivuta-Ramona BADITA, student
Ana STOCHIOIU, chemist
Constantin IVAN, physicist
Iani-Octavian MITU, physicist engineer
Ion TUDOR, college engineer
Constantin CENUSA, electronics engineer
Aurelia CELAREL, student
Laurentiu SERBAN, mathematician - programmer
Mihaela Florenta LAZAR, staff
Cristiana-Daniela BARSAN, staff
Doina STANCIU, student
Ana PANTELICA, physicist
Maria-Diana MIHAI, physicist
Paul-Alexandru IONESCU, physicist engineer
Gherghina Stan, staff