Office for Nuclear Regulation

ONR guidance

The following guidance is used by ONR Inspectors to ensure that nuclear licensed sites will remain safe against the potential effects of climate change.

ONR guidance Relevance
Safety Assessment Principles (SAPs) The primary purpose of the SAPs is to provide ONR's Inspectors with a framework for making consistent and effective regulatory judgements about the safety of activities.

One of ONR's key expectations outlined in the SAPs is that the reasonably foreseeable effects of climate change over the lifetime of a facility should be taken into account.
External Hazards Technical Assessment Guide (TAG 13) TAGs support the SAPs. The External Hazards TAG, known as TAG 13, provides ONR Inspectors with guidance on the consideration of natural and man-made hazards.

An overview of ONR's climate change considerations is provided in the TAG 13 Head Document, with further information available in Annex 2 (Meteorological Hazards) and Annex 3 (Coastal Flood Hazards).
Use of UK Climate Projections 2018 (UKCP18) by the GB Nuclear Industry The Position Statement on UKCP18 is supported by ONR, the Environment Agency, Natural Resources Wales and the Scottish Environment Protection Agency.

The Position Statement sets out the regulators' expectations with regard to UKCP18 and their application by dutyholders in the nuclear industry when undertaking climate change assessments in support of safety cases.
Principles for Flood and Coastal Erosion Risk Management The Joint Advice Note from ONR and the Environment Agency provides advice on how flood and coastal erosion risk issues are considered when reviewing proposals for nuclear new build developments in England.

The principal documents through which flood risk is reported by dutyholders are the Flood Risk Assessment (FRA), that is prepared for the planning process and assessed by the EA, and the nuclear safety case(s). The EA provides advice on how to account for climate change when assessing flood risk, via the guidance Flood risk assessments: climate change allowances.