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Cheers to the "unloved children of ITER"

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This week, the 100th meeting of the Configuration Control Board was held ...
"No more PCRs! No more Project Change Requests!" This statement was heard many times during the recent meeting of the ITER Council Management Advisory Committee. Indeed, PCRs are not very welcome in ITER as they may be the source of additional costs. Therefore, "No further PCRs!" is a worthwhile goal.
 
Unfortunately as complex designs evolve, changes are unavoidable, making PCRs necessary. For Krystyna Marcinkiewicz, who coordinates the PCR process together with Thomas Tellier and Eloise Boyer, these "unloved children of ITER" are to be looked after with care.
 
The PCR procedure at ITER allows design changes to be formally introduced and approved. Proposals for modification—whether pertaining to technical scope, cost or schedule—are written up as PCRs and stored in one common database. Minor PCRs are dealt with by ITER's Design Integration Section, whereas the major PCRs are discussed at the bi-weekly Configuration Control Board (CCB) meeting. CCB has permanent members representing the senior management of all offices and departments at ITER, and the seven Domestic Agencies.
 
To make sure that only absolutely necessary change requests end up on the Board's table, the draft PCRs are screened by Chief Engineer Joo-Shik Bak before a number is attributed to them. Some drafts get turned down immediately, some are discussed but not accepted for further study, and some are dropped after thorough investigation.
 
The usual path, however, is for a standard PCR to be formulated, accepted for study, approved for implementation and implemented. One of the most ambitious and complex PCRs in ITER history was PCR-200, accepted for study three years ago in order to establish the current Project Baseline.
 
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... followed by a glass of champagne and a toast from Chairman Rem Haange, ITER Deputy Director-General (here with Mark Robinson, Krystyna Marcinkiewicz and Nenne Jakvik).
When in 2001 the ITER Final Design Report (FDR 2001) was agreed to, it constituted the basis for the selection of the ITER site and for negotiations concerning the sharing of packages and responsibilities for the in-kind procurement among the parties involved. Since 2001, the Baseline has changed in several significant ways and required its re-establishment. This happened through PCR-200: technical improvements to the design were introduced to comply with safety regulations and to reduce technical risks of not achieving the prescribed performance of ITER. PCR-200 has been subject to regular status reporting and review at CCB for over half a year and was finally approved on 4 May 2010 and endorsed by the Council afterwards.
 
The scope of PCRs is broad; their study and implementation can take years or hours. The fastest PCR was dealt with in 24 hours. The oldest, PCR still "alive" was first discussed in January 2007 when the design of major ITER systems was reviewed. It concerns the atmosphere and vent detritiation systems, the ultimate safety barrier in ITER to strictly limit tritium releases.
 
In order to improve reliability and performance, and to eventually meet all the safety requirements, the technology basis for the detritiation systems and its configuration had to be changed. A comprehensive R&D program is still ongoing in the Domestic Agencies, with very promising and successful results. Demonstration of the fully integrated detritiation system performance will ultimately be carried out, but by that time this PCR will be history.
 
At present, with one of the main schedule drivers being the construction of the ITER buildings, the relevant PCRs are under severe examination. Recently, for the main Tokamak Complex, a strict deadline was agreed to. As the implementation of PCRs will be dealt with on a floor-by-floor basis, any PCR regarding the roof of the Tokamak Complex will have to be closed by March 2013.
 
But before dealing with the future, this week it was time to pause for thought ... and to celebrate the 100th meeting of the Configuration Control Board with a glass of champagne.