Informal workshop on radionuclide laboratories. Issue 1

The network of radionuclide stations in the International Monitoring System (IMS) of the Comprehensive Test Ban Treaty (CTBT) will be comprised of 80 monitoring stations and 16 laboratories acting in support of the monitoring stations. The 16 radionuclide laboratories have been designated but there are issues to resolve in several areas: - Fee structure and payments to the laboratories from the PTS; - Agreement on Detailed requirements for certification of the laboratories; - Duties of the laboratory To help provide technical information in these and other areas an Informal Workshop was held on January 29th - February 2nd 2001 at Atomic Weapons Establishment (AWE) United Kingdom. It was agreed that a common fee structure would make for a more efficient operation if one could be agreed. One possible fee structure for payment to the laboratories was considered to be an annual fixed fee for service (estimated at $38,000) plus a charge for each individual analysis (estimated at $1,200). These estimated values were based on the laboratory replies to a questionnaire organised by the PTS in December 2000. An average of 40 samples/year/ laboratory was considered to be the number required to maintain support to the monitoring station network and also maintain the laboratory capability. Based on this number the overall cost, payable to the laboratories, of running a network of 16 radionuclide laboratories was estimated at $1.38M per year, when all 80 radionuclide stations are operational. The first proficiency test exercise had been carried out in November 2000 and was discussed. Overall the results were highly encouraging and any minor problems found were being addressed. The technical areas requiring further consideration were uncertainty values and cascade summing corrections. The basis for an ongoing programme of such exercises was discussed and agreed by participants. One recommendation that came out of this meeting was the desirability of using a common nuclear data set and the one chosen was the Brookhaven Nuclear Data. Presentations were given on their current status on behalf of most of the laboratories present at the meeting. The conclusions drawn from these presentations were that in the main technical problems connected with carrying out the measurements were resolved. The main problems remaining concerned preparing documentation for certification, setting up communication protocols and obtaining clarification on some of the certification issues. It was agreed that INF.96 should be finalised as soon as possible so that certification of all labs could take place to the same standard and also contracts between the labs and the PTS could be set up. Laboratories were asked to supply PTS with a date by which they could be ready to commence certification The draft certification document INF.96 was considered in detail and apart from the changes detailed in this report, participants accepted the document. There were several minor changes to be made to the detailed technical content of INF.96/Rev.1 22 January 2001. These had the effect of clarifying the requirements and ensuring that they were deliverable by the laboratories. Section 3.2 (Data quality Objectives) of that document was discussed and was accepted as a recommendation rather than a mandatory requirement. The position was clarified with respect to the need for a Laboratory Information Management System (LIMS). As long as the information required by the PTS was available, each laboratory was free to set up its own system. It was also decided that bar-coding of samples would be strongly recommended but not mandatory. In this way, there should be no delay in obtaining certification. It was agreed that each laboratory was responsible for developing and implementing its own Quality System using the criteria laid down in INF.96. Specific items of local responsibility were security policy, data archiving and data manipulation. Communication protocols were discussed and it was agreed that PTS would issue all required formats. Until then, each laboratory could communicate according to the contents of the draft format presented by the PTS. PTS also accepted responsibility for devising an authentication mechanism. Other matters that were agreed as a PTS central responsibility included requests by states parties for data and for further measurements, choice of laboratory for any level 5 measurements and storage of non-level 5 filters. The Quality Control of monitoring stations by the radionuclide laboratories was discussed and the use of Be-7 as the main QC nuclide agreed. A proposal was made to send QC filters to two laboratories consecutively rather than split the filter. It was also proposed that the QC frequency should be one per quarter per station with the proviso that, in the event of a disagreement this should change to one per month until resolution. It was also stated that PTS were in process of modifying the station gamma spectrometer efficiency calculations to take into account cascade summing by Co-60 and Y-88. Several matters concerning the monitoring stations were discussed including a review of WGB TL2-20, which was stated to require revision to reflect the current position. A presentation was given to show that Ra-224 should be removed from the CLPS monitoring list of nuclides. The Command and Control structure was discussed and was said to be due for discussion in WGB(15). Some other matters were discussed including the expansion of analytical techniques beyond non-destructive gamma spectrometry. The fundamental need to limit information to that useful to support the treaty was stressed but it was accepted that there should be a continual assessment of possible technologies