The Atmospheric Dispersion Modelling Liaison Committee held a one-day workshop on 12 March 2020 at the Centre for Radiation, Chemicals and Environmental Hazards (CRCE), PHE, Oxfordshire.

The aim of the workshop was to bring together dispersion modellers, policy experts and decision-makers to discuss the role of dispersion modelling in emergency planning and response across different contaminant types. Key objectives were to:

• Look at current practices in emergency planning and response modelling across different contaminants, including radiological, chemical, volcanic ash, fire and smoke.
• Assess the differences in scientific approaches and explore reasons for these, for example whether they arise from historical development, or from the nature of the underlying emergencies (timescales, distances affected, ease of identifying the contaminant etc)?
• Examine differences in planning at a policy level (the use of ‘reasonable worst case’, probabilistic approaches) and any implications of this for response.
• Discuss whether emergency response and planning can benefit from joint working – and, if so, how this could be taken forward.

The Committee have drafted a record of the discussions which took place during the seminar, also detailing the four questions posed to the audience and attendees answers to those questions: ADMLC seminar QandA Discussion Sessions v1.1.

The workshop included talks from distinguished speakers including Professor Robin Grimes FRS FREng (MOD Chief Scientific Advisor), Professor Jonathan Rougier and representatives from the Met Office, Public Health England, Office for Nuclear Regulation and the Health and Safety Executive. The programme is attached. And links to the presentations are listed below:

• ADMLC Chairman’s welcome
• Introduction – modelling perspectives
• Perspectives on emergencies involving atmospheric releases
• The application of atmospheric dispersion modelling for the provision of health protection advice in the event of a radiological incident
• The practical use of models during the emergency response to chemical incidents and fires
• Responding to volcanic eruptions
• Outline of approaches in the National Risk Register and Resilience Direct
• What is the reasonable worst case?
• REPPIR approach to consequence assessment and associated risk framework
• How dispersion modelling informs public safety decision making for risks presented by major hazards installations

If you have any comments and feedback relating to the seminar please notify ADMLC at admlc@phe.gov.uk.