Wednesday 9^th May 2007
National Physical Laboratory

Present:

Chairman:		Pete Burgess		National Physical Laboratory
Secretary:		Clare Lee		National Physical Laboratory
		Duncan Aston		High Technology Sources
		David Bate		British Nuclear Group
		Keith Baxter		MoD MNCQP
		John Bennett		DSTL
		Reg Bosley		Nukem
		Derek Brazer		AWE
		Ludovic Chevallereau		Serco Assurance
		Robin Crosse		Thermo Fisher Scientific
		Bill Croydon		Radiation Watch Ltd
		Tim Daniels		HPA, Radiation Protection Division
		Paul Deacon-Smith		St Thomas’s Hospital
		Denise Delahunty		RRPPS, Birmingham
		David Gallacher		St Thomas’s Hospital
		Andy Galpin		Nukem
		Julian Ginniver		UKAEA, Dounreay
		James Grand		Berthold Technologies (UK) Ltd
		Norman Heffernan		Velindre Hospital
		Chris Hill		Thermo Fisher Scientific
		Michael Hodgson		Thermo Fisher Scientific
		Steven Judge		NPL
		John Locke		Serco Assurance
		Duncan McClure		HPA, Radiation Protection Division
		Jan McClure		HPA, Radiation Protection Division
		Frank McGurty		UKAEA
		Robert Newiss		Nukem
		Steve Newton		BIL Solutions
		Mairin O’Colmain		Radiological Protection Institute of Ireland
		Max Pottinger		Thermo Electron Corporation
		Mike Renouf		British Nuclear Group
		Tony Richards		Consultant
		James Roberts		Velindre Hospital
		Sue Ryan		New Cross Hospital
		Keith Simmons		MoD Nucleonic Calibration QP Committee
		John Simpson		Nukem
		Bill Snooks		Pycko Scientific Ltd
		Sinclair Tait		RWE Nukem
		Graeme Taylor		NPL
		Jon Wardle		AWE
		Graham Whish		Addenbrooke's Hospital
		Eliot Williams		UKAEA
		Mike Woods		IRMC

33.1  Welcome

Pete Burgess (NPL) welcomed members to the 33rd meeting of the IRMF and summarised the agenda for the meeting.

The minutes of the 32nd meeting were agreed to be an accurate record of the meeting. There were no matters arising.

33.2  Medical X-ray Comparison

Denise Delahunty (RRPPS) explained that the UK diagnostic X-ray community used two traceable primary standards:

• NPL (used by RRPPS in Birmingham); and
• PTB in Germany (used by John Perry Laboratory at St George’s in Tooting and most European instrument manufacturers).

The secondary standard laboratories (RRPPS and John Perry) then calibrated most of the operational instruments in use in the UK. The instruments chosen for the comparison exercise were used to check the output of X-ray sets and scatter generated during use.

33.3  Gamma Dose Rate Comparison

Duncan McClure (HPA) reported that all the measurements had been completed, with the exception of AWE which had been “missed out” for some reason. Further, there had been problems with the SmartIon and it was to be returned to RRPPS for a repeat measurement.

Little progress had been made on the comparison report due to the resignation of Martin Palmer from NPL, however Martin Kelly had recently taken over. All participants were asked to send their results to Duncan with the aim that they would be provisionally reported during the November meeting.
Action: Clare Lee to arrange for the instrument to be sent to Jon Wardle

33.4  Neutron Monitor Comparison

Graeme Taylor (NPL) reported that there were 6 participants for the 4th neutron comparison exercise. Only NPL had been able to make measurements due to problems with the instruments.

33.5  GPG on Calibration and Testing of Electronic Personal Dosemeters

Jan McClure (HPA) informed the meeting that she was is in the process of fleshing out the draft document, adding detail to the original framework. The document split instruments into 3 categories: bleepers, simple dosemeters and multi-function, multi-detector dosemeters. The tests proposed for them became demanding as the intended use of the instrument got more demanding. The document recognised however, that the tests employed might be reduced as experience with an instrument type grew, if no failures were detected.

Jan asked John Bennett (DSTL) and NPL to assist her in completing the draft - this was understandable, given her substantially increased workload since the Litvinenko poisoning incident.

In the discussion that followed, the point was made that purchasers tended to buy dosemeters that were too clever for their application, unnecessarily burdening themselves with training problems and high testing costs. Pete Burgess pointed out that the role of the QP in advising the employer was vital (see section 33.10 of these minutes).

33.6  Basic Surface Contamination Comparison

Pete Burgess (NPL) apologised for not having organised a repeat contamination exercise due to pressure of work. The planned comparison would use the same instruments and measurement protocol as the previous exercise, to minimise effort.

Mike Woods (IRMC) emphasised that the results of the exercise are needed quickly, Pete agreed. Denise Delahunty (RRPPS) suggested a large area detector should also be included in the exercise, but Pete said no, because of the time pressure.
Action: Clare Lee to email a registration form to IRMF members

33.7  Investigation into the Poor Results from the Last Surface Contamination Monitoring Comparison

Pete Burgess (NPL) apologised that this too had not been progressed further due to pressure of work. However, the project, to determine the reason(s) for such variable results, would start soon. Initial possibilities included:

• Poor source uniformity
• Instrument reading uncertainty (both instruments were “waggly needle” types with sparsely marked displays)
• Spacing errors
• Instrument non-linearity
• Emission rate errors

The investigation would be run by Pete, assisted by Andy Stroak from NPL. John Bennett (DSTL), John Simpson (Nukem), Duncan McClure (HPA) and Denise Delahunty (RRPPS) volunteered to join the working group.
Action: Pete Burgess to arrange a start-up meeting

John Simpson (Nukem) pointed out that poor source uniformity (variations of up to 30 % from the mean over a 10 cm2 area) had been why Nukem used a mask for each detector and measured the corresponding emission rate. Pete responded that this would have helped a lot but was not a perfect solution. A poor uniformity over the area employed would couple with detector non-uniformity to produce a deviation from the true average efficiency. This was most likely to be a problem for short range emissions.

There was a discussion on identification of non-uniformity during which it was stated that QSA, the major manufacturer, measures this as part of their quality control process but does not release the results.

Jon Wardle (AWE) volunteered to check the uniformity of any sources used in the last comparison exercise, free of charge, if they were delivered to and collected from him.  He believed this would address many of the issues in the results from the last exercise.

33.8  Revision of ISO Standards

Tony Richards (Leeds) reminded the meeting that he was a member of the BSI working group on ISO standards revision. He stated that two standards of interest to the IRMF, ISO 7503 and ISO 8769, were being discussed at present.

ISO 7503-1 (Evaluation of surface contamination - Part 1: Beta-emitters (maximum beta energy greater than 0,15 MeV) and alpha-emitters) had been redrafted but was rejected, as it was unnecessarily complicated. A further draft had been written and this prompted major discussions. There was to be a vote at the next meeting on which of the drafts would be developed. Tony had some copies of the latest document and was happy to send one to members who wished to comment. Members should contact him at agrichards@f2s.com to receive a copy.

ISO 8769 (Reference sources for the calibration of surface contamination monitors - Beta-emitters (maximum beta energy greater than 0,15 MeV) and alpha-emitters) had been “reconfirmed” approximately 3 years ago and so had not been revised. Tony had since approached the national committee to request it be reviewed. He expected his request to be supported. The aim is was to combine ISO 7503 and ISO 8769 into one new standard.

Mike Woods (IRMC) stated that he had been “moaned at” for years about these standards and had started the ball rolling to revise them. He wanted to combine the two and tighten up the non-uniformity limit. The 1988 edition required a standard deviation of less than 10 % for a set of 10 cm2 (maximum) areas covering the source. This requirement allowed for the possibility of one area being more than 30% lower than the mean, in extremis, for a 150 cm2 source. Mike said that he would like the source calibration certificate to include uniformity data in the form of a map. He suggested that source manufacturers should be included in the review process to ensure that any specification produced was achievable. However, the consensus of the meeting was that manufacturers might aim to ensure that they were able to continue using an existing process, rather than make improvements. Mike stated that spectral degradation, the correlation between activity and emission, the nuclides suggested and the conditions of use also should also be included in the discussion of a revised document. Mike announced that he was meeting with a small working group and asked for members to email him their comments before July. He could be contacted at mike.woods@blueyonder.co.uk

Tony ended his presentation stating that draft standards depend on consensus between national committees and there will be an opportunity for public comment later in the process.
Action: Tony Richards to give a presentation on the ISO revision process at the next meeting

Mike Renouf (BNG) pointed out that these standards were very important in flask movements across Europe. Pete Burgess emphasised the opportunity for IRMF to influence and be seen to influence international standards.

33.9  Revision of GPG14

Pete Burgess (NPL) had reviewed all comments that had been received and was working his way through the document making changes appropriately. The major changes were:

• Acknowledgment of the 1999 IRRs
• The virtual removal of the contiguous portions section
• Incorporation of specific guidance on dual purpose probes
• Revision of testing after repair

Pete emphasised the need for any further comments to be sent immediately. Any areas where there was disagreement with, or between, the comments received would be discussed with those who provided the comments.
Action: All members to send any further comments to Pete Burgess

Once completed, the draft would be circulated to members in pdf format. Members would then have an opportunity to comment prior to the final working group meeting. A list of members from whom comments had been received (during the whole revision process) would also be made available.

Max Pottinger (Thermo Fisher Scientific) encouraged NPL to ensure GPGs were reviewed every 5 years, as originally stated.

33.10  Qualified Person Accreditation

Pete Burgess informed the members that he and Clare Lee had attended a meeting of the RPA2000 accreditation committee to discuss the introduction of QP accreditation in a parallel way to the RPA and Laser Protection Advisor (LPA) processes. NPL had presented a draft list of competencies to the RPA 2000 group that had generally been accepted.

The formal appointment of the QP had existed in the past but it had been abandoned. The IRRs (1999) and the associated code of practice and guidance clearly indicated that the QP had a formal and significant role (see paragraphs 356 to 359). It was quite clear that expertise beyond that of a bench engineer was demanded.

A discussion ensued and questions were asked on how competency would be assessed and who would assess it. An initial guess at the number requesting accreditation was between 50 and 100, mainly IRMF but with additional IPEM and AURPO members.

Mike Renouf (BNG) described the approach at Sellafield, where they had essentially 3 levels of qualified persons, reaching down to quite junior levels. The general consensus of the IRMF members was that QP status was not appropriate for the less qualified and experienced people and that they should be treated by SQEP assessment.  It was essential that any such approach would be acceptable to regulators.
Action: Pete Burgess to contact RPA2000 group and request permission to email the QP definition and draft competencies to IRMF members for development 

View the presented role and responsibilities of the QP ( PDF 43 KB)

33.11  NPL Programme Formulation

Steven Judge (NPL) explained that programme formulation was under way at NPL, how the process worked and the part IRMF members could play in it. The Measurement Advisory Committee Working Group had prioritised the draft programme and the latest version of it was available on the NPL website. 

The final decision on the programme content would be taken after public consultation in July. Comments from members, both positive and negative, were encouraged. When asked about their inclusion, Steven emphasised that primary standards were a major part of the programme but that some projects relating to homeland security had already been cut.

Steven went on to describe the recent structural changes to NPL, these were:

• Ionising Radiation and Acoustics had merged into one programme
• Realignment to focus on some technical areas and emerging technologies
• Movement towards a centralised Measurement Services Group for some of the more routine measurements

Steven invited anyone with comments or reservations about these to contact him: steven.judge@npl.co.uk

Jon Wardle (AWE) stated that NPL was up to 3 times as expensive as PTB. Steven pointed out the different financial approach PTB were able to use.

Steven summarised the different ways in which NPL could help with measurement problems, such as the 'Measurement for Innovators' scheme, and the opportunities for secondments of staff to and from NPL.

View Steven Judge's presentation ( PDF 658 KB)

33.12  Polonium and the Litvinenko poisoning

Duncan McClure, Jan McClure and Tim Daniels (HPA) described HPA’s monitoring and monitoring control role following the Litvinenko poisoning. Due to the complexity and sensitivity of the information presented, they have been asked to prepare minutes of their presentation. These will be added once available.

33.13  Any Other Business

Robin Crosse (Thermo Fisher Scientific) explained that the tremendous bringing together of several organisations had lead to significant duplication of probe designs. The range had been rationalised to reduce the duplication and also to remove probes based on anthracene, which is unpleasant chemically. He stated that probes would be available with either PET or MHV connectors. Thermo Fisher Scientific would continue to support other probe designs for as long as parts are available. Click for further information

The next meeting will be held on Thursday, 29th November 2007.

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