Office for Nuclear Regulation

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Control of Radiation Exposure

Executive summary

Purpose of intervention

The Office for Nuclear Regulation (ONR) is undertaking a series of Control of Occupational Radiation Exposure (CORE) interventions across all of the nuclear licensed sites in the UK with the following objectives:

Regulation 8 of IRR99 is concerned with the restriction of exposure to ionising radiations. It requires radiation employers to restrict, So Far As Is Reasonably Practicable (SFAIRP), the exposure of employees and other persons to ionising radiation. The main aim of the Regulations and the supporting Approved Code of Practice (ACOP) is to establish a framework for ensuring that exposure to ionising radiation arising from work activities is kept As Low As Reasonably Practicable (ALARP) and does not exceed dose limits specified for individuals.

Interventions Carried Out by ONR

This intervention at the Sellafield Site adopted the same, consistent approach that is to be used for all IRR99 Reg.8 interventions across the industry. The intervention was segregated into two elements: the first element to assess the general arrangements for restricting worker exposures under Regulation 8, and the second element to involve the inspection of work areas and activities in order to ensure that the arrangements are being applied at the point of work.

A standard questionnaire (which is to be used for all IRR99 Reg.8 interventions) was issued to the licensee in advance of the site inspection. The licensee completed the questionnaire and we discussed its responses during the first part of the site inspection so that we could form a view on the adequacy of its arrangements. The remaining part of the site inspection involved a visit to facilities and operational teams to determine whether the licensee's arrangements were being effectively applied at the point of work.

We rated each aspect of the licensee's arrangements that were inspected during the intervention using the ONR Integrated Intervention Strategy (IIS) rating system. These ratings are provided in the Annex of the report. An overall rating was also allocated.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable to this intervention.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

The licensee provided evidence that it is compliant with Regulation 8 of the Ionising Radiation Regulations 1999 to reduce operational exposure to As Low As is Reasonably Practical, hence the overall rating of adequate.

The licensee had adequate arrangements in place with regard to dose targets and investigation, the trending of dose and radiological survey data, the reporting and reviewing of radiological events, providing information, instruction and training, and benchmarking.

We noted that there was some inconsistency with regard to the application of the Licensee's application of Local ALARP Review Levels (LARLs). Rather than being used as a level of dose that will trigger a review of an employee's working practices in order to ensure that their exposure is ALARP, we encountered several examples of the LARL being used a limit which must be avoided by either reallocating the individual to other work or raising the LARL so that it would not be exceeded. In the latter case, the justification for raising LARLs was not always adequately recorded. Consequently we have raised an issue recommending that the Licensee review its application of the LARL system so that it is fit for purpose.

We also considered the barriers and signage around some contamination controlled areas to be below standard and have raised an issue which recommends that they are improved.

The aforementioned issues relate only to occupational radiation exposure and have no impact on nuclear safety. They will be taken forward as normal regulatory business.

Conclusion of Intervention

From the evidence gathered during this intervention, we do not believe there are any matters that currently impact on nuclear safety. We are of the opinion that the licensee has demonstrated adequate compliance with Regulation 8 of IRR99, and consequently we have allocated an overall rating of 3 (adequate) for this intervention in accordance with the IIS.