The construction stage of a nuclear power plant overlaps other stages such as design and commissioning. The responsible organization may establish separate organizations for these stages or combine them under one orga­nization. In any case, the responsibilities and interfaces shall be clearly defined and the status of the plant established.

The responsible organization should identify the person who will occupy the position of head of the construction organization and who will have the overall responsibility for the construction activities. That person should have enough authority and resources to assume the responsibilities of ensuring that construction and installation activities will be carried out in accordance with the applicable requirements and planned programmes.

During the construction stage of a nuclear power plant the main quality — related activities performed are the following:

• Preparing safe working procedures

• Monitoring the activities of all personnel on site

• Planning and coordinating the activities

• Controlling and supervising suppliers

• Carrying out a maintenance programme for equipment that could deteriorate

• Perform a pre-service inspection to obtain the baseline for future in­service inspections

• Arranging the handover between suppliers and organizations.

Whilst the construction organization shall retain responsibility for coordinating and planning the overall construction of the plant, suppliers should be responsible for producing detailed plans and for obtaining the approval.

Considering the number of organizations and companies usually involved in the construction phase, it is necessary that interface arrangements are agreed between participants. Examples of interfaces to be defined in writing are the following:

• Construction organization with suppliers, operating organization, prin­cipal designer, sitting organization and Regulatory Body

• Suppliers with sub-suppliers and with test and commissioning organization.

The construction stage is the previous step for the commissioning period. That is why provisions should be made by the construction organization to control and coordinate the handover of completed works between suppliers and to the commissioning organization. These provisions should include the following:

• A planned and orderly transfer of responsibilities for structures, systems and components

• That documentation of transferred items is complete, accurate and con­tains all non-conformances identified and solved

• Official transfer, signing of documents after a joint check of items and records.

More detailed considerations about the commissioning stage can be found in Section 21.6 and in Chapter 22.

A graded approach, based on the significance for safety, may be applied to the following activities:

• Qualification of special processes and associated personnel

• The need for, the detail and the degree of control of inspection plans

• The level of traceability.