Working Party on Criticality (WPC) Home page

Latest News

June 2020: The WPC e-room has been closed and replaced by a group on the NDA Hub.

November 2020: The following Good Practice Guides have been issued (see NDA Hub)
  • Good Practices in the use of Criticality Codes
  • Minimum Subcritical Margins

Who We Are

The Working Party on Criticality (WPC) is a non-executive UK national committee focusing on criticality safety issues up to, but not including, experimental and in-core power reactor operations. WPC is a formal sub-group of the Safety Directors Forum.
The issues considered are relevant to fabrication, transportation, storage and other operations relating to nuclear materials (e.g. new build, enrichment, reprocessing, decommissioning and long-term waste management).
  • WPC Scope and Objectives
  • WPC Members
    • WPC members comprise Nuclear Site Licensees and other organisations with an interest in criticality safety.
  • WPC Sub-groups
    • WPC has a number of sub-groups to cover specific topic areas. Participation in sub-groups is not restricted to WPC members. Current groups include:
      • Criticality Assessment of Fissile Wastes
      • Nuclear Codes and Data
      • Fault Analysis techniques
      • Learning from Experience
      • Organisational Criticality Health
      • Criticality Emergency Planning
  • WPC Workshops
    • WPC run an annual workshop to provide opportunities for less experienced practitioners to gain experience on a wide range of technical issues. The workshops also provide an opportunity to improve communication between less experienced members of the criticality community. Participation in workshops is open to all with an interest in criticality safety, not just WPC members.
  • WPC Papers
      • Since the 1970s over 290 WPC papers have produced. These cover a range of topics from:
        • Meeting reports
        • Formal WPC position papers
        • Sub-group reports
        • Technical papers contributed by members to document their activities for future reference.
        • Good Practice Guides (library of Good Practice Guides
          • Good Practices in the use of Criticality Codes
          • Minimum Subcritical Margins
          • Good Practice Guide to Criticality Detection at UK Nuclear Licenced Sites

    What is Criticality Safety?

    For a brief introduction to what criticality safety is all about see the following: What is Criticality Safety?

    Forthcoming Events  

    WPC Meeting              TBA
    ANSWERS Seminar    25-27 May 2021
    ANS Annual Meeting   13-17 June 2021    Providence, Rhode Island