ANSI 58.23:2007 pdf download.American Nuclear Society.
transient ignition source: Temporary ignition source that is usually associated with, but not limited to, maintenance or modifications involving combustible and flammable liquids, wood and plastic products, waste, scrap, rags, or other combustibles resulting from the work activity.
uncertainty: A representation of the confidence in the state of knowledge about the parameter values and models used in constructing the PRA ANSl/ANS-58.21-2007 [1] and ASMERA-2002/RA-Sb-2005 [2]).
verify: To determine that a particular action has been performed in accordance with the requirements of this standard, either by witnessing the action or by reviewing records (ANSI/
ANS-58.21-2007 (1]).
walkdown: Inspection of local areas in a nuclear power plant where structures, systems, equipment, and cables are physically located in order to ensure accuracy of procedures and drawings, equipment location, operating status, and environmental effects or system interaction effects on the equipment that could occur during accident conditions (ASM E-RA-2002/ RA-Sb2005 [21 and ANSI/ANS-58.21-2007 [1]).
3 Fire PItA application process
3.1 Purpose
This section describes a process to determine the capability of a Fire PRA to support a particular application of risk-informed decision making. Fire PRA capabilities are evaluated for each SR. rather than by specifying a capability level” for the whole PRA. Therefore, only those aspects of a Fire PRA element required to support the application in question need the capability level appropriate for that application. The process is intended to be used with PRAs that have had a peer review that meets the requirements of Sec. 6.
This standard adopts the PRA application process as set forth in Sec. 3 of ASME-RA-2002/ RA-Sb-2005 [2]. The remainder of this section provides, as needed, an interpretation of the ASME-RA-2002/RA-Sb-2005 121 requirements to suit the Fire PRA context as compared to the Internal Events PRA context.
The process flowchart as presented in Fig. 3.1-1 ofASME-RA-2002/RA-Sb-2005 [21 and the general process description as presented in Sec. 3.1 of ASME-RA-2002/RA-Sb-2005 [21 are adopted in whole and without exception as applicable to Fire PRA applications with the following remark:
• In the context of Fire PRA, wherever Sec. 3 of ASME-RA-2002/ RA-Sb-2005 [21 uses ‘PRA,”“Fire PRA” is substituted.
3.2 Identification of application (box A)
This standard adopts the discussion of identification of Application” as provided in Sec. 3.2 ofASME-RA-2002/RA-Sb-2005 [2] in whole with the following remarks:
• In the context of Fire PRA, ‘plant design” SHALL be interpreted to include the provisions of the plant fire protection program;
• In the context of Fire PRA, “plant activities” SHALL be interpreted to include any and all activities associated with the maintenance of fire protection systems and features, compliance with administrative aspects of the fire protection program, fire-specific compensatory measures, the training of plant personnel specific to fire, and the actual response of plant personnel to a fire event, as well as those activities related to the maintenance and operation of the SSCs required for safe shutdown.
3.3 Assessment of PItA for necessary scope, results, and models (box B)
3.3.1 Necessary scope and results
This standard adopts this aspect of the overall process description as provided in Sec. 3.3.1 of ASME-RA-2002/RA-Sb-2005 [2] in whole.
3.3.2 Modeling of SSCs, activities, and fire protection systems and features
This standard adopts the discussion of the “Modeling of SSCs and Activities” as provided in Sec. 3.3.2 ofASME-RA.2002/RA-Sb.2005 [2] in whole with the following addition:
• In addition to SSCs and activities, the assessment of Fire PRA model requirements and acceptability SHALL include a like treatment of fire protection systems and features impacted by the plant design or operational change.
