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AP1000 reactor design computer design

Designer (requesting party): Westinghouse

Current position: Assessment of reactor design complete. Design Acceptance Confirmation issued in March 2017.

Timeline: pr-Sep 2007 - Step 1 (preparatory step) Sep 2007 - Jun 2008 - Step 2 (initial assessment) Jun 2008 - Dec 2009 - Step 3 (detailed assessment) Jan 2010 - Dec 2011 - Step 4 (detailed design, safety case and security evidence assessment) Dec 2011 - Westinghouse paused GDA activities with 51 outstanding issues remaining Aug 2014 - Westinghouse recommenced GDA of the AP1000® March 2017 - DAC/SoDA Issue

Progress reports

At the end of each step of the assessment, the regulators publish detailed technical reports and a summary report.

Find out more about progress reports

Regulatory issues and resolution plans

A regulatory issue is a serious regulatory shortfall identified by the regulators. The issues are potentially significant enough to prevent provision of design acceptance. There were two regulatory issues published for the AP1000®.

Full details of the ROs for AP1000® are contained in the technical assessment reports.

Regulatory issue title RI ref.
Information required by the Environment Agency for the detailed assessment stage RI-AP1000-0001 PDF
Civil Engineering Design Methodology RI-AP1000-0002 PDF
GDA issues 

There were 51 GDA Issues raised following the Interim Design Acceptance (iDAC) in 2011. For each of these issues Westinghouse published resolution plans to outline how the intended to address the issue.

More on GDA issues.

Design acceptance

In March 2017, ONR and the Environment Agency the AP1000© design a Design Acceptance Confirmation and Statement of Design Acceptability.

Find out more about DAC/SoDA.

Office for Nuclear Regulation Environment Agency Natural Resources Wales