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IMS Radionuclide Laboratory GBL#15 IMS Radionuclide Laboratory GBL#15 GBL#15 team : C L Comley, P Thompson, A V Davies, J McLarty, M Ball, C Miles, J Collins AWE Aldermaston, Reading, Berkshire, RG7 4PR, UK RADIONUCLIDE LABORATORIES AND THE CTBT TREATY THE ROLE OF CERTIFIED LABORATORIES The certified laboratories role is to re-measure with better sensitivity any samples containing fission and activation products that are indicative of a nuclear test and to re-measure QA/QC samples collected at any of the 80 radionuclide particulate stations. HISTORY AND PROGRESS OF THE UNITED KINGDOM GBL#15 AT AWE Experts from the UK participated in the negotiations at the CD in Geneva until 1996, providing advice on the capability required by the treaty to monitor worldwide radionuclide’s from a nuclear event. PROTOTYPE INTERNATIONAL DATA CENTRE The laboratory contributed to the PIDC in Arlington USA, by sending weekly data from a particulate station located at UKAEA Chilton UK, operated by the UK Environment Agency for Department Environment Food & Rural Affairs and measured at GBL#15. PROGRESS TO CERTIFICATION AS GBL#15: The existing laboratory had the expertise and relevant equipment to meet the specification of a CTBT laboratory. GBL#15 currently uses 2 broad energy detectors. The experience and equipment of the laboratory including the staff was reviewed by PTS before progressing towards certification as the UK radionuclide laboratory. Following the preparation of relevant documentation to meet the specification in INF-96, participation in PTS proficiency tests and a visit by the PTS, addressing observations by the quality assessor and the PTS, the lab was certified in December 2004 and commenced working on a fee for service as part of the IMS. PTE-2008 Detector GBL15_143 Filter Type CANA Filter Dimensions 50mm x 5mm Acquisition Time 200,000 seconds The protocol states that the radionuclide monitoring stations shall be supported by laboratories, which shall be certified by the Technical Secretariat in accordance with the relevant operational manual for the performance, on contract to the Organisation and on a fee for service basis, of the analysis of samples from radionuclide monitoring stations. Article IV of the CTBT Treaty states that the International Monitoring System shall comprise radionuclide monitoring including certified laboratories and this shall be placed under the authority of the Technical Secretariat and operated by the States hosting or otherwise taking responsibility for them in accordance with the protocol. INFORMAL CTBT RADIONUCLIDES LABORATORIES WORKSHOPS (2001, 2008) Two informal CTBTO radionuclide workshops have been hosted by GBL#15 (Jan/Feb 2001 and Dec 2008), where the 16 CTBT laboratories have met and progress in the operations has been made. The workshops provide an excellent environment for experts and the PTS to discuss technical Issues and make recommendations for the future development of the IMS laboratory and continued effective operations. BENEFITS OF COMPTON SUPPRESSED DETECTOR AWE uses a Compton Suppressed detector for low background measurements. The spectra below show the difference between spectra recorded normally and with Compton Suppression. As can be seen the continuum is considerably reduced on the suppressed spectrum allowing identification of peaks that would normally be lost in the noise. Care must be taken in reporting results to allow for those nuclides having gammas in cascade. NOBLE GAS MONITORING Xenon measurement stations forms part of IMS radionuclide verification network and are intended to measure ultra-low levels of radio- xenon isotopes in the atmosphere from underground and atmospheric tests and to identify background levels from industrial processes around the world. GBL#15 is currently investigating the possibility of obtaining a capability to measure ultra-low levels of xenon fission products and to contribute to CTBTO as one of the noble gas laboratories. Unsuppressed sample Suppressed sample Unsuppressed sample Suppressed sample © Crown Copyright (2009) This document is of United Kingdom origin and contains proprietary information which is the property of the Secretary of State for Defence. It is furnished in confidence and may not be copied, used or disclosed in whole or in part without prior written consent of the Intellectual Property Rights Group (IPRG), Defence Procurement Agency, Poplar 2A #2218, Abbey Wood, Bristol, BS34 8JH, England. In the workshop in December 2008, the objectives and goals included discussions on proficiency test exercises (PTE), results and future plans, discussions of relevant parts of the Operation Manual and the sharing of experiences and techniques at the laboratories including advances on gamma spectrometry and noble gas measurements. The report to WGB32 included a recommendation from the workshop participants to develop technical details of the PTE tests and the definition of unsuccessful performance and report back to WGB with the results of its deliberation.
