Frequently Asked Questions
What is the UK Working Party on Criticality (WPC)?
The UK Working Party on Criticality (WPC) is a non-executive national committee focussing on criticality safety issues up to, but not including, experimental and in-core power reactor operations. 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).
Who can participate in the WPC and how is it structured?
The WPC is open to organisations and individuals actively working in the field of criticality safety in the UK, including nuclear site licensees and supply chain organisations. The Office for Nuclear Regulation (ONR) sits as an observer on the committee. The WPC operates through a main working group and specialist sub-groups that focus on areas such as computational modelling, professional development, and other industry good practice .
What does the WPC produce or publish?
The WPC develops and maintains technical guidance and good practice documents on criticality safety, often reflecting consensus across UK industry. It also contributes to international standards development, hosts workshops, and shares updates relevant to criticality safety assessments, training, and code validation.
How does the WPC contribute to nuclear safety in the UK?
By fostering collaboration and technical exchange across the nuclear sector, the WPC helps ensure consistent, high standards in criticality safety practices. Its outputs support regulatory compliance, enhance assessor competence, and strengthen the UK’s capability in managing fissile material safely.