Office for Nuclear Regulation

This website uses non-intrusive cookies to improve your user experience. You can visit our cookie privacy page for more information.

Heysham 1 Planned Inspection - SB127 Reactor Safety System Trip Parameters

Executive summary

Purpose of intervention

This was a planned inspection of EDF Energy Nuclear Generation Limited’s (NGL’s) Heysham 1 power station (HYA), undertaken as part of the planned intervention strategy for the Civil Nuclear Reactor Programme (CNRP) of the Office for Nuclear Regulation (ONR).

The work was carried out in line with the planned inspection programme contained in the Heysham 1 Integrated Intervention Strategy (IIS).

Interventions Carried Out by ONR

A Control and Instrumentation (C&I) Principal Inspector and I (C&I Specialist Inspector) carried out a Systems Based Inspection (SBI) of the reactor safety system trip parameters.

The intervention was performed in line with ONR’s guidance requirements (as described in our technical inspection guides) in the areas inspected.

Explanation of Judgement if Safety System Not Judged to be Adequate

The reactor safety system trip parameters were judged to meet the requirements of the safety case and were adequate.

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

We carried out a system based inspection of the reactor safety system trip parameters and concluded that:

LC10 (training) – IIS Rating 4 (below standard). Weaknesses were identified with the administrative arrangements for training of sampled staff maintaining and operating reactor safety system trip parameters. Shortfalls in the data accuracy of the training records management system were identified and actions put in place to resolve these issues. Two regulatory issues have been raised and will be tracked under ONR’s issues database system (ONR issue nos. 3259 and 3261).

LC23 (operating rules) – IIS Rating 3 (adequate). From the evidence sampled during this inspection, we were satisfied that safety case conditions and limits had been correctly identified, and where necessary had been incorporated in the Technical Specifications.

LC24 (operating instructions) – IIS Rating 3 (adequate). From the evidence sampled during this inspection, we were satisfied that adequate operating instructions were in place to support plant operations. A minor shortfall was found in an operating instruction relating the operation of the reactor on 3 quadrants and an action was placed on the Licensee to rectify this. This action will be tracked under ONR’s issues database system (ONR issue no. 3262).

LC27 (safety mechanisms, devices and circuits - SMDC) – IIS rating 3 (adequate). From the evidence sampled during this inspection, we were satisfied that the reactor safety system trip parameters are regarded as SMDC and were being managed accordingly and adequately maintained by suitably qualified and experienced people so that compliance with LC27 was demonstrated through compliance with LC10, LC23, LC24 and LC28.

LC28 (examination, maintenance, inspection and testing) – IIS Rating 3 (adequate). From the evidence sampled during this inspection, we were satisfied that the reactor safety system trip parameters were maintained with adequate systems in place to document the maintenance requirements.

Conclusion of Intervention

From the evidence sampled during this system based inspection against LCs 10, 23, 24, 27 and 28 for the reactor safety system trip parameters, we consider that the requirements of the safety case have been adequately implemented at Heysham 1.

There are no findings from this inspection that could significantly undermine nuclear safety.