A Review of Nrc Instrumentation Needs

The accident at Three Mile Island highlighted the need to make improvements in nuclear power plant instrumentation. Since the accident, the Nuclear Regulatory Commission has required the installation of new equipment aimed at improving both post accident monitoring capability and the operator/equipment interface. Replacement of some existing equipment with qualified, highly reliable sensors and processing equipment will satisfy many of the new requirements. But implementation of other requirements will be more difficult. New measurement techniques must be developed or use of new technologies must be judged acceptable for safety purposes before some instrumentation needs can be satisfied. The lack of commercially available equipment has caused reassessment of the importance of other instrumentation needs. Looking beyond those modifications needed to correct deficiencies discovered as a result of the TMI experience, improvements in the reliability of normal plant operating equipment should be considered to reduce the frequency of safety system challenges. Advanced instrumentation presently available or under development may be useful in identifying equipment degradation, thereby preventing major equipment failures and consequent plant upsets. There is also a need for better diagnostic tools for improving the operator's response capability following plant upsets. Some of these tools are now available but others which show considerable promise require more development effort. Although significant improvements in safety may be possible through implementation of improved instrumentation, those improvements can be made only if the industry supports the development effort with both money and manpower.