Performance of nuclear power plant or automated system depends on operator´s availability

The levels of operator cognitive and sensomotor availability are measured during normal nuclear plant operation at full power four times a day. The time distribution of the average production level is a system performance indicator. Mathematical models of the connection between system performance and human availability have been developed. The level of operator real availability depends on the work complexity. The effectiveness of rule- and skill-based behavior is determined by the level of sensomotor availability. The effectiveness of knowledge-based behavior is determined by the level of cognitive capacity. The mathematical model explains the impact of human availability and behavior on system performance. Organizational analysis determines possible organizational paths for increasing human availability in everyday operational situations.