There must be a record of the investigations and what they found. You must keep these records in accordance with your local procedures and with Regulation 8(3). This is regardless of whether an incident needs to be notified to the appropriate enforcing authority or not.

For notifiable SAUE incidents, you must send a report on the outcome of the investigation to the appropriate enforcing authority. Investigations of SAUE incidents should include:

• what happened 
• an estimate of the dose(s) received by the exposed individual(s)
• a detailed account of the causes and contributory factors
• whether any similar previous incidents have occurred where individuals might have been over or under exposed, or if there are any trends that show a possible systematic failure
• whether local procedure relating to CSAUE, required under Regulation 8(1), schedule 2(l), has been applied if the SAUE meets the threshold for being clinically significant
• any learning from the incident investigation, corrective measures that have been adopted and how this has been shared

In summary, incidents reported to the IR(ME)R enforcing authorities must show sufficient evidence of an appropriate level of investigation to provide reassurance that the risk of the incident recurring is reduced as far as reasonably practicable.

You must redact names of individual people in the report to comply with UK data protection legislation.