Expert Supervision

Expert Super Vision

Both the construction and the operation of a nuclear facility are subject to supervision by the respective nuclear supervisory authority responsible which is to check upon compliance with licensing prerequisites, requirements and provisions of the licences and other legislative rules. For this purpose, representatives of the supervisory authority or experts consulted have the right to enter the facility at any time and have access to any necessary information from the operator.

For this purpose, the operator submits information operating reports to the authority at regular intervals and notifies the authority of reportable events according to the nuclear safety officer and reporting ordinance, in particular of any excess of fixed operating parameters (limiting values) and advises each change in personnel responsible for operation management and control as well as all results of in-service inspections. In the case of special events as with the case of important in-service inspections, the experts consulted in the licensing procedure are also called upon during the supervisory procedure by order of the supervisory authority.

There are three different decision categories for modifications of the plant:

The modification is subject to a licence by the licensing authority;
The modification requires approval by the supervisory authority;
The modification can be performed by the operator and is to be reported to the supervisory authority.
Supervision of construction

The experts consulted by the licensing authority are entrusted with the inspections of the layout of nuclear facilities and pertinent systems and components as well as accompanying control during construction. The accompanying control consists of examining the documents of the manufacturer or applicant by using regulatory works, specifications and possible additional conditions imposed by the licensing authority with regard to compliance with requirements (stated as documents review and approval) as well as compliance of the components or a system with the previously reviewed documents in the course of the in-process surveillance. This examination is denoted as source surveillance or quality control inspection.

The applicant for a licence for the construction and operation of a nuclear plant has to take the necessary precautions against damage due to construction and operation of the plant. This includes the assurance of the required quality of plant components. The applicant must ensure the required quality assurance measures to be taken by the plant vendors and manufacturers. The quality assurance activities by the authority or the experts consulted do not replace the quality assurance measures of the applicant or manufacturer.

Thus, the quality assurance (QA) for construction and operation of a nuclear plant consists of the following parts:

QA of the applicant.
QA of the plant vendor.
QA of the manufacturer for products, components and systems.
The accompanying control is required for all safety-relevant systems and components as regards nuclear power plants e.g. for:

Reactor pressure vessel with internals including fuel elements and control rods;
All other components pressurised with primary coolant (e.g. steam generator, pressurised, reactor coolant pumps, reactor coolant lines);
All components pressurised with radioactive fluids;
Items pressurised in the secondary system;
Main steam and feed water pipes;
Reactor protection system;
Instrumentation and control systems;
Refuelling and transport equipment for control rods and fuel elements;
Emergency power supply systems;
Lifting and load-carrying equipment;
Physical protections systems.