Critical Design Review Radiation Monitors for PSS1 at ESS L. Johansson, Stuart Birch, Per Persson, Duy Phan, Lali Tchelidze CERN review, 1 March 2017

Review Objectives Based on the deliverables listed in Appendix 1 and presentations given during that CDR, the Review Committee is asked to answer the following charge questions:  Have system requirements been defined and are they complete and adequate enough to ensure acceptable system performance? Is the proposed design expected to meet the functional and performance requirements, and are interfaces properly identified and defined?  Have appropriate options and alternatives been considered in selecting the design approach? Are there further value engineering opportunities that should be considered? Are the technical specifications sufficiently mature to proceed to procurement? Have major project risks and safety hazards been identified, characterized, and mitigated where appropriate?

Review conference 1 March 2017 8 Feb 2017: PSS1 Rad monitor specifications for ESS sent to CERN. 24 Feb 2017: Comments received from CERN review committee. This meeting will address these comments. Next steps; Review report addressing the charges (CERN). Reply addressing the review (ESS).

Schedule Wednesday, 1 March 2017 09:00 - 09:20 Introduction 20' ( Christinehof ) (LJ) 09:20 - 09:40 Overview PSS1 20' (SB) 09:40 - 10:00 Radiation fields 20' (LT) 10:00 - 10:20 Radiation detectors 20' (LJ) 10:20 - 10:40 PSS1 Monitors 20' (SB) 10:40 - 10:55 Break 10:55 - 11:55 Response to questions and comments 1h0' 11:55 - 12:00 AOB, End of meeting Presentations from ESS are given by Stuart Birch, Lena Johansson and Lali Tchelidze https://indico.esss.lu.se/event/765/

ESS response to CERN specific comments Markus Widorski and Daniel Perrin from CERN have returned 63 specific comments to the ESS specification documents. These will be addressed by the following ESS colleagues: Stuart Birch: Comment MW2, 3, 4, 7, 19, 38-63. Lali Tchelidze: Comment MW5, 8 – 14. Lena Johansson: Comment MW6, 15, 16, 17, 18, 20, 21, 22 – 37.

CERN general comments In terms of ’safety reliability’ it should be made clear for which system function a certified reliability is required and why. The receiving system must be able to guarantee a similar or higher level of reliability. The terminology and structure should become clearer in the document (what is a monitor ? what is the system ? what is the detector ?) Parts of the specified requirements come from the technical description of a specific product. Did you check that this is effectively what you need and is it always consistent with other parts of the document? Given the time constraints you have, you might effectively try to target your specification on an identified product, which does satisfy your basic requirements - rather than compiling a wish list of functions, where it might be difficult for a provider to reply or which involves development works. ESS will address this during discussion

Thank you!