Recently discovered safety system problems resulting from air system deficiencies

Conference · Sun Jan 01 04:00:00 EST 1989 · Transactions of the American Nuclear Society; (USA)

OSTI ID:6528370

Ornstein, H L

In March 1987, the US Nuclear Regulatory Commission's (NRC's) Office for Analysis and Evaluation of Operational Data (AEOD) issued a case study report on air systems problems. The case study report highlighted 29 significant events involving safety-related systems in US plants that resulted from degraded or malfunctioning non-safety-grade air systems. The case study noted that air systems are not safety-grade systems at most operating plants. As a result, plant accident analyses assume that safety-related equipment dependent on air systems will either fail safe upon loss of air or perform its intended function with the assistance of backup accumulators. The failures have shown that in many instances safety-related equipment dependent on air systems did not fail safe upon loss of air or perform its intended function with the assistance of backup accumulators. The root causes of most of those failures were traceable to design and/or maintenance deficiencies. In August 1988, the NRC issued a generic letter to all licensees. The generic letter requested that licensees review their plant air systems in accordance and perform design and operations verifications of the instrument air systems. Numerous air systems deficiencies were found by the licensees in the course of responding to generic letter 88-14. Many of the deficiencies that could have seriously hampered plant responses to design-basis events had existed for many years.

• OSTI ID: 6528370
• Report Number(s): CONF-891103--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (USA) Journal Volume: 60
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200 -- Nuclear Reactor Technology-- Components & Accessories
220900* -- Nuclear Reactor Technology-- Reactor Safety
ACCIDENTS
ACCUMULATORS
CONTAINERS
ENGINEERED SAFETY SYSTEMS
FLUID MECHANICS
MAINTENANCE
MECHANICS
NUCLEAR FACILITIES
NUCLEAR POWER PLANTS
PERSONNEL
PNEUMATICS
POWER PLANTS
REACTOR ACCIDENTS
REACTOR INSTRUMENTATION
REACTOR MAINTENANCE
REACTOR OPERATORS
REGULATIONS
SURVEILLANCE
TANKS
THERMAL POWER PLANTS
TRANSIENTS