The workshop was hosted by the French Institute for Radiological Protection and Nuclear Safety (IRSN) and the Nuclear Energy Agency (NEA)

General information

The Nuclear Energy Agency (NEA) Committee on the Safety of Nuclear Installations (CSNI) Working Group on Fuel Cycle Safety (WGFCS) held an international workshop on Chemical Hazards in Fuel Cycle Facilities Nuclear Processing. The workshop was hosted by the IRSN in co-operation with the United States Nuclear Regulatory Commission (US NRC) and the NEA on April 17-19 2018 in Boulogne-Billancourt near Paris, France. The workshop lasted three days.

Objectives

Working under the mandate of the CSNI, the objective of the WGFCS is to advance the understanding for regulators, technical support organisations (TSOs) and operators of relevant aspects of nuclear fuel cycle safety in NEA member countries.

The objective of this workshop is to discuss and review national activities, safety and regulatory approaches for managing chemical hazards at fuel cycle facilities (FCFs), the effectiveness of these activities, and areas for improvement.

Background

The chemical forms of nuclear material used in FCFs as well as the chemicals and processes used in nuclear material processing can introduce chemical toxicity hazards as well as reactive chemical hazards. A wide variety of chemical hazards is considered in the design, construction, operation and decommissioning of FCF’s.

In 2011, the WGFCS held a workshop, “Safety Assessment of Fuel Cycle Facilities – Regulatory Approaches and Industry Perspectives.” Recommendations from this workshop recognised the importance of the impact of chemical hazards on safety assessments of FCFs. Additionally, the WGFCS members agreed that there was a benefit for the fuel cycle community to identify best practices for chemical safety within the nuclear industry and other industrial sectors, such as the chemical industry.

Scope and content

FCFs should be designed and operated in a manner that ensures that the risks of hazardous chemical exposure, corrosion, fire, explosion and contamination are controlled and minimised. The evaluation of chemical risks for FCFs is important to the safety of nuclear processing. Consequently, assurance of safety requires control of both the chemical and nuclear hazards.

Chemical safety hazards can occur across the spectrum of FCFs including uranium conversion facilities, uranium enrichment facilities, all types of fuel fabrication facilities, irradiated material processing facilities and waste management operations. 

The workshop discussed potential regulatory issues involving chemical processing of nuclear materials operations as well as safety issues regarding accidents prevention and mitigation of the potential consequences (chemical and possibly radiological) for the workers, the public and the environment. The workshop was centred on the following technical focus areas:

Session 1: Regulations, standards, requirements and guidance for chemical safety for FCF’s, including:

• review of national approaches and practices;
• chemical exposure standards;
• similarities/differences between the nuclear industry and the chemical industry,  if any.

Session 2: Consideration of chemical hazards for the design, commissioning, operation and decommissioning of FCFs, including:

• identification of postulated initiating events;
• review of methods and tools for estimation and safety assessment/reassessment of chemical risks and releases;
• review of national approaches to determine the tolerability of the toxicological consequences compared to chemical exposure standards;
• good practices for the safe management of chemical risks;
• human and organisational factors regarding processing of chemicals;
• detection and alarm capabilities for chemical releases.

Session 3: Emergency preparedness and response in case of accidental situation due to chemical hazards in FCFs, including:

• jurisdictional interfaces and decision-making process for large site facilities relevant to different regulations (nuclear/chemical hazards);
• identification of design extension conditions (especially in consideration of post-Fukushima Daiichi safety reviews);
• application of calculation methods and monitoring of chemicals in case of accidental release;
• prevention and mitigation of consequences;
• guidelines and emergency planning.

Session 4: Operating experience feedback on managing chemical hazards in FCFs, including:

• review of significant events and lessons learnt;
• research and development needs;
• future challenges for new FCFs on chemical safety.

Format and outline

The workshop included an introductory session, four technical sessions devoted to presentations by participants on the topics identified above and a final session. The final session summarised the discussions and developed conclusions and recommendations for possible further CSNI actions.

All participants were expected to take part in the discussion and in the formulation of conclusions in the final session.

Workshop proceedings

Proceedings of the workshop will be published and will include full papers and presentations from the opening session and all technical sessions, conclusions and recommendations from discussions in panel sessions and the final summary session of the workshop.

Organising committee