@book{e2d13b5605794281adcd3a8b66643e40,
title = "Connection between PRA and RI-ISI analyses",
abstract = "In-service inspections are applied to safety important pipe components in nuclear power plants (NPPs) to ensure their reliability. In Finland, in-service-inspections are planned carefully so that the risk of nuclear accident, employees' exposure to radiation and the cost of inspections are in balance and within acceptable limits. This approach is called risk informed in-service-inspection (RI-ISI). Probabilistic risk assessment (PRA) is used to calculate the quantitative risk of nuclear accident and analyse the importance of different systems and components. PRA's main purpose is to support risk informed decision making. PRA also supports RI-ISI analyses so that it quantifies the consequences of pipe failures and provides risk importance measures for pipe components. The purpose of this report is to study how PRA and RI-ISI analyses could support each other better. New development ideas include automatic piping failure consequence calculation in PRA software, extending PRA model to account for piping in more detail and developing PRA's time dependent analysis. It would be possible to develop an integrated software tool for RI-ISI and PRA. It could be beneficial to update PRA and RI-ISI simultaneously, especially if the analyses were more integrated. Uncertainty analysis could also be performed in RI-ISI in the same way as in PRA.",
keywords = "risk-informed in-service-inspections, probabilistic risk assessment, nuclear safety, pipe",
author = "Tero Tyrv{\"a}inen",
note = "Project code: 101984 ",
year = "2015",
language = "English",
series = "VTT Research Report",
publisher = "VTT Technical Research Centre of Finland",
address = "Finland",
}