The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis (open access)

The Effects of Degraded Digital Instrumentation and Control Systems on Human-system Interfaces and Operator Performance: HFE Review Guidance and Technical Basis

New and advanced reactors will use integrated digital instrumentation and control (I&C) systems to support operators in their monitoring and control functions. Even though digital systems are typically highly reliable, their potential for degradation or failure could significantly affect operator performance and, consequently, impact plant safety. The U.S. Nuclear Regulatory Commission (NRC) supported this research project to investigate the effects of degraded I&C systems on human performance and plant operations. The objective was to develop human factors engineering (HFE) review guidance addressing the detection and management of degraded digital I&C conditions by plant operators. We reviewed pertinent standards and guidelines, empirical studies, and plant operating experience. In addition, we conducted an evaluation of the potential effects of selected failure modes of the digital feedwater system on human-system interfaces (HSIs) and operator performance. The results indicated that I&C degradations are prevalent in plants employing digital systems and the overall effects on plant behavior can be significant, such as causing a reactor trip or causing equipment to operate unexpectedly. I&C degradations can impact the HSIs used by operators to monitor and control the plant. For example, sensor degradations can make displays difficult to interpret and can sometimes mislead operators by making it …
Date: February 26, 2010
Creator: O'Hara, J. M. & W. Gunther, G. Martinez-Guridi
Object Type: Report
System: The UNT Digital Library
Federal Register, Volume 75, Number 38, February 26, 2010, Pages 8795-9084 (open access)

Federal Register, Volume 75, Number 38, February 26, 2010, Pages 8795-9084

Daily publication of the U.S. Office of the Federal Register contains rules and regulations, proposed legislation and rule changes, and other notices, including "Presidential proclamations and Executive Orders, Federal agency documents having general applicability and legal effect, documents required to be published by act of Congress, and other Federal agency documents of public interest" (p. ii). Table of Contents starts on page iii.
Date: February 26, 2010
Creator: United States. Office of the Federal Register.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Afghanistan Casualties: Military Forces and Civilians (open access)

Afghanistan Casualties: Military Forces and Civilians

This report collects statistics from a variety of sources on casualties sustained during Operation Enduring Freedom (OEF), which began on October 7, 2001. OEF actions took place primarily in Afghanistan; however, OEF casualties also includes American casualties in Pakistan, Uzbekistan, Guantanamo Bay (Cuba), Djibouti, Eritrea, Ethiopia, Jordan, Kenya, Kyrgyzstan, the Philippines, Seychelles, Sudan, Tajikistan, Turkey, and Yemen.
Date: February 26, 2010
Creator: Chesser, Susan G.
Object Type: Report
System: The UNT Digital Library