The effect of plant aging on equipment qualification and human performance issues related to license renewal

Research into the causes and effects of nuclear power plant aging as obtained through the assessment of operating experience and testing has raised questions regarding the adequacy of existing industry standards for addressing the concerns raised by this research. The authors discuss these issues, with particular emphasis on equipment qualification and human performance. The results of research completed through the US Nuclear Regulatory Commission´s NPAR (Nuclear Aging Research) Program demonstrate that the aging process is significant for electrical, control, and instrumentation (ECI) devices, even those located in mild environments. To maintain the high reliabilities expected of these devices, nuclear power plant staffs must expand their existing environmental qualification programs to address the aging that has occurred and that will be experienced during the license renewal term. This may require additional maintenance, testing, and monitoring. The human performance issues that are raised both by plant aging and by the programs being proposed to address plant aging are discussed, and the effects of changes in staff composition are examined.<>