Ionizing Radiation Metrology at NMIJ/AIST and ENEA-INMRI

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1 Ionizing Radiation Metrology at NMIJ/AIST and ENEA-INMRI Pierino De Felice and Marco Capogni - ENEA C.R. Casaccia Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti (ENEA-INMRI) Roma ITALY Yoshio Hino and Norio Saito National Metrology Institute of Japan, Advanced Industrial Science and Technology (NMIJ/AIST) Tsukuba JAPAN Contribution to the Italy in Japan 2011 initiative Science, Technology and Innovation

2 ENEA-INMRI in ITALY The National Institute of Ionizing Radiation Metrology (INMRI, belongs to the Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) and it acts as the National Metrology Institute for ionizing radiation quantities in Italy, based on the role given to ENEA by the Italian Law No. 273/1991. The Institute is responsible for developing and providing the Italian national standards relating to ionizing radiation quantities. The standards are needed to guarantee the reliability of ionizing radiation measurements at the national level, in all field of interest, along with their international traceability. Potential national users: Radiotherapy and radiodiagnostic medical centers, Regional Agencies for environmental protection, National bodies for radiological surveillance and control (in particular ISPRA), Defence and protection bodies, Producers, manufacturers and end-users of radioisotopes or ionizing radiation measuring instruments

3 NMIJ/AIST in JAPAN The Metrology Institute of Japan (MIJ) and The Metrology Management Centre both of which are part of the National Institute of Advanced Industrial Science and Technology (AIST), together make up the National Metrology Institute of Japan (NMIJ) ( Those two equally important NMIJ organizations cooperate with each other for NMIJ to function as a single institution in charge of measurement standards. The NMIJ/AIST in cooperation with the International Metrology Cooperation Office and Metrology Training Center, conducts research and development towards the establishment of primary standards (measurement standards), and dissemination of the measurement standards to societies and industries. MIJ also carries out technological tasks to link the national measurement standards with those of other countries. At the same time, MIJ performs tasks for the government to maintain the accuracy of measuring instruments necessary for all types of business, taxation, safety and regulations.

4 ENEA-INMRI and NMIJ/AIST: BIPM The two NMIs cooperate at the international level under the auspices of the Bureau International des Poids et Mesures (BIPM) which coordinates the research activities of the NMIs in the words by ensuring worldwide uniformity of measurements and their traceability to the International System of Units (SI). The BIPM does this with the authority of the Meter Convention, a diplomatic treaty between 55 nations, and it operates through a series of Consultative Committees, whose members are the NMIs of the signatory States.

5 ENEA-INMRI and NMIJ/AIST: ICRM At the International level the two Institutes collaborate also for the research activities carried out in the frame of the International Committee for Radionuclide Metrology (ICRM) ( The two Institutes strongly supported the activities of the ICRM Executive Board providing in recent past officers for main functions like President and Secretary. Many scientific activities, international conferences and publications that represent fundamental references for radioactivity measurement community worldwide were organized in collaboration by the two NMIs in the frame of the ICRM. In the frame of this cooperation, the 18th ICRM Conference on Radionuclide Metrology and its Applications was held in Japan (Tsukuba) on September 2011 ( ICRM 2011

6 ENEA-INMRI: Air-kerma standard The Air-kerma standard in the low-energy (10 kv to 50 kv) and medium-energy (50 kv to 300 kv) x-ray range is based on two free-air ion chambers, figures (a) and (b) respectively. (b) (a)

7 ENEA-INMRI: personal dose equivalent standard ISO phantoms for personal dose equivalent standard for x and gamma ray (Cs-137 & Co-60) beams. (b)

8 ENEA-INMRI: Primary Activity Standards Standard of Activity for β and β-γ emitting nuclides, based on 4πβ-γ coincidence counting systems Standard of Activity for γ emitting nuclides, based on NaI(Tl) well type detector

9 ENEA-INMRI: Secondary Activity Standards Standard of Activity for γ emitting nuclides, based on a welltype ionisation chamber (high precision secondary standard) Standard of Activity for x and γ emitting nuclides, based on three HPGe γ- ray spectrometers (high precision secondary standard)

10 ENEA-INMRI: Radon and Neutron Standards Manganese sulfate bath for neutron emission due to Am-Be and 252 Cf sources Standard of thermal neutrons flux density Standard of Activity Concentration for 222 Rn-in-air based on a 1m 3 radon chambers.

11 NMIJ/AIST: Air-kerma standards The NMIJ standards of Air-kerma are based on free-air ion chambers in (a) the low-energy and mammography x-rays (10 kv to 50 kv) and (b) medium-energy x-rays (50 kv to 300 kv), and on graphite cavity chambers in gamma-rays Cs-137 Co-60 W/Al Mo/Mo Mo/Rh Rh/Rh (c) gamma-rays (a) low-energy and mammography x-rays (b) medium-energy x-rays

12 NMIJ/AIST: Absorbed dose to water standard Co-60 absorbed dose to water standard is based on a graphite calorimeter in figure (a). NMIJ is developing absorbed dose to water standard for high energy x-rays from a clinical linear accelerator in figure (b) (b) clinical linear accelerator (a) graphite calorimeter

13 NMIJ/AIST: Activity standards Activity Standard based on a 4πβ-γ coincidence counting system Activity Standard for x and γ emitters based on a HPGe γ-ray spectrometer and NaI(Tl) welltype scintillation spectrometer Activity Standard for γ emitters based on well-type ionization chambers

14 NMIJ/AIST: Activity standards Activity Standard for pure α/β emitters based on liquid scintillation counters Surface emission rate Standard for a large area source of a/b emitters based on a multiwire proportional counter Activity Standard of radioactive gas based on a set of five inner-through type proportional counters

15 NMIJ/AIST: Neutron standards Fast neutron fluence (cm -2 ) Accelerator-based Monoenergetic Spectra 24, 144, 565keV, 2.5, 5.0, 8.0, 14.8MeV Radioactive Source-Emitted Spectra 241 Am-Be, 252 Cf Thermal neutron fluence rate (cm -2 sec -1 ) Graphite pile thermal neutron field Neutron emission rate (sec -1 ) 241 Am-Be, 252 Cf Van de Graaff accelerator Cockcroft-Walton accelerator Graphite Pile 1.9m x 2.3m x 1.9m Neutron Irradiation Room 11.5m x 11.5m x 11.5m