Fire PRA Cable Selection (Task 3)
Contents
Task Overview
Background
This task provides instructions and technical considerations associated with identifying cables supporting those components selected in Task 2. In previous Fire PRA methods (such as EPRI FIVE and Fire PRA Implementation Guide) this task was relegated to the SSD analysis and its associated databases. This document offers a more structured set of rules for selection of cables.
Purpose
Conducting a Fire PRA in accordance with this procedure necessitates an analysis of fireinduced circuit failures beyond that typically conducted during original Fire PRAs. The circuit analysis elements of the project are conducted in three distinct phases:
- Fire PRA cable selection (Task 3),
- Detailed circuit failure analysis (Task 9), and
- Circuit failure mode likelihood analysis (Task 10).
This chapter provides methods and instructions for conducting the first phase of circuit analysis–selecting Fire PRA cables (Task 3). The purpose of Task 3 is to identify for all Fire PRA components the circuits/cables3 associated with the components and the routing/plant location of the identified circuits/cables. These relationships can then be used to determine the Fire PRA components potentially affected by postulated fires at different plant locations.
In most cases, it is advantageous to perform some or all of Task 9 (detailed circuit failure analysis) coincident with Task 3. The degree to which Task 3 and Task 9 are combined is highly dependent on numerous plant-specific factors. Considerations for combining the two tasks are incorporated in relevant sections of Chapter 3.
Scope
Chapter 3 provides methods and technical considerations for identifying cables to be included in the Fire PRA Cable List. This task contains the following key elements:
- Identify cables associated with Fire PRA equipment,
- Determine plant routing and location for the Fire PRA cables,
- Identify Fire PRA power supplies, and
- Correlate Fire PRA cables to Fire PRA equipment and plant locations (fire compartments and/or fire areas).
Implementation of plant-specific quality assurance and configuration control requirements that might apply to a Fire PRA is not within the scope of this task. Nor does this task address validating the accuracy of plant-specific data extracted from plant drawings, documents, or databases. Each plant should follow appropriate quality assurance, administrative, and configuration control procedures applicable to the work conducted. The need to validate input source documents should be addressed as part of assembling the prerequisite information.
