[en] Technical Specifications (TS) in a nuclear power plant are specific requirements on its day-to-day operation, designed to protect public health and safety. Two primary aspects of the TS are (1) limiting conditions of operation (LCO) with allowed outage times (AOTs) and (2) surveillance testing intervals (STIs). In recent years, there has been growing interest in the nuclear community in reexamining the TS. One of the reasons is that a significant portion of reactor downtime (plant unavailability) is attributable to the strict TS. Existing TS were derived from engineering judgement based on deterministic review; they were not directly risk-based, and their efficacy in enhancing public safety is difficult to establish. This paper presents a summary of a critical review of the Westinghouse report which proposed that AOTs for a number of safety systems at the Byron Generating Station be increased from 3 to 7 days