<p>The Office for Nuclear Regulation's (ONR) incident notification process requires dutyholders to state their judgement on the significance of an incident as major, moderate and minor in an initial incident notification form. Incidents could relate to safety, nuclear security and/or safeguards.</p><p> </p><p>This categorisation is the dutyholders’ initial perspective when they first reported the incident. This means that a “major incident notification form” does not necessarily align with a “major incident”. ONR’s guidance is that the dutyholders should use the plain English interpretations of the words and their judgement on the significance of the incident. ONR inspectors use the dutyholders’ perspective as one aspect of the diverse information that informs their judgements on the significance of incidents.</p><p> </p><p>ONR reports each financial year on the number of incident forms it has received, including the dutyholders’ initial perspective on incident significance, in annex 3 of the <a href="https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.onr.org.uk%2Fdocuments%2F2023%2Fcni-annual-report-2023.pdf&data=05%7C02%7CParliamentary.PQ%40energysecurity.gov.uk%7C1ac773b5d2e64a2d09a008dc3c33ae60%7Ccbac700502c143ebb497e6492d1b2dd8%7C0%7C0%7C638451439870366959%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=Rnzdv4x097CRg5%2FYxsECesDy8%2BagRRI7XDy4bz7YKuU%3D&reserved=0" target="_blank">Chief Nuclear Inspector’s Annual Report on Great Britain’s Nuclear Industry 2022/23 (onr.org.uk)</a>.</p><p> </p><p> </p><p>Summary of dutyholders’ reports received 2015 to present:</p><p> </p><table><tbody><tr><td><p>Financial Year</p></td><td><p>Minor</p></td><td><p>Moderate</p></td><td><p>Major</p></td></tr><tr><td><p>2015/16</p></td><td><p>300</p></td><td><p>11</p></td><td><p>2</p></td></tr><tr><td><p>2016/17</p></td><td><p>514</p></td><td><p>33</p></td><td><p>2</p></td></tr><tr><td><p>2017/18</p></td><td><p>571</p></td><td><p>60</p></td><td><p>1</p></td></tr><tr><td><p>2018/19</p></td><td><p>578</p></td><td><p>50</p></td><td><p>1</p></td></tr><tr><td><p>2019/20</p></td><td><p>707</p></td><td><p>39</p></td><td><p>4</p></td></tr><tr><td><p>2020/21</p></td><td><p>642</p></td><td><p>57</p></td><td><p>1</p></td></tr><tr><td><p>2021/22</p></td><td><p>855</p></td><td><p>47</p></td><td><p>3</p></td></tr><tr><td><p>2022/23</p></td><td><p>644</p></td><td><p>82</p></td><td><p>5</p></td></tr><tr><td><p>2023/24*</p></td><td><p>491</p></td><td><p>60</p></td><td><p>3</p></td></tr></tbody></table><p>*up to 28/02/2024</p><p> </p><p>Source: ONR Information management system</p>