As mentioned earlier, selecting and implementing HSIs is only one small part of the overall engineering effort of the NPP. However, the control room and the HSI

are so tightly integrated with the overall architecture of the plant and, together with the operators, play such a vital role in plant efficiency and safety that it should be treated with the same rigorous engineering discipline as all other parts of the plant. Designers therefore need to attend to all areas of analysis, design and implementation that affect human interaction with plant and systems. We know that operator performance in a control room may be equally influenced by the design of the control system software, the system architecture, the physical architecture of the control room or the design of procedures and documentation. To address these issues, it is necessary to integrate human factors considerations into the processes used for the design of the technical system.

NUREG-0711 emphasises the importance of following a formal engineering process also for all human factors elements of the plant and to provide traceable documentation for all design decisions. This requires designers to compare the final HSIs, procedures and training with the detailed description and specifications of the design to verify that they conform to the planned design resulting from the HFE design process and verification and validation activities (O’Hara et al., 2012).

This section describes the key aspects of an integrated approach to HFE that will ensure that the technology and design choices will actually serve the purpose for which they were selected.