Nuclear Energy Agency (NEA) Technical opinion papers (TOPs) are the summary consensus of experts for a particular topic in the field of nuclear safety. They are the result of work carried out under the aegis of the Committee on the Safety of Nuclear Installations (CSNI). The first TOP was released in 2002. Topics addressed in TOPs have included: Fire Probabilistic Safety Assessment (PSA); Recurring Events; Human Reliability Analysis in PSA for Nuclear Power Plants; Managing and Regulating Organisational Change in Nuclear Installations; Living PSA and its Use in the Nuclear Safety Decision-making Process; Development and Use of Risk Monitors at Nuclear Power Plants; Level-2 PSA for Nuclear Power Plants; The Role of Human and Organisational Factors in Nuclear Power Plant Modifications; Better Nuclear Plant Maintenance: Improving Human and Organisational Performance; Research on Human Factors in New Nuclear Plant Technology; Loss-of-Coolant Accidents Criteria Basis and Test Methodology; Nuclear Licensee Organisational Structures, Resources and Competencies: Determining their Suitability; Ageing Management of Nuclear Fuel Cycle Facilities; and Defence in Depth of Electrical Systems.