Maintenance and Testing Errors in Nuclear Power Plants: A Preliminary Assessment

Abstract

Safety and reliability in the operation of nuclear power plants have been topics for intense analysis and debate in recent years. Once crucial factor which has received little attention until very recently, is human reliability in the operation, maintenance and testing of nuclear plants. Maintenance and testing errors are of particular importance in that, despite the fact that they are relatively few in number compared with hardware related events, their occurrence programs the system for future operator errors bv introducing erroneous data in operator-hardware system communication or by eliminating a portion of that communication. Erroneous data or a lack of anticipated feedback following control actions by the operator can tend to cause further inappropriate responses and to escalate the frequency of operator errors. Such effects are most undesirable during emergencies.

A number of improvements based upon improved human factors engineering will be necessary to eliminate maintenance errors of the type encountered in this study. These include: standardization of design for given types of subsystems, standardization of maintenance operations, work simplification involving both physical and psychological aspects of maintenance work, the use of training simulators to increase the amount of practice in performing maintenance operations, automanual control to show predicted outcome of results, assignment of individual responsibility and accountability to specific hardware subsystems, measures of job performance against some criterion, programmed instruction, improved divisions of responsibility among maintenance, operating and technical personnel, and improved management practices.