Exporting to SAPHIRE for Probabilistic Risk Assessment (PRA)
Introduction#
FRI3D integrates with SAPHIRE (Systems Analysis Programs for Hands-on Integrated Reliability Evaluations) to enable comprehensive Probabilistic Risk Assessment (PRA) workflows.
This integration allows hazard, fire, and physical simulation data generated within FRI3D to be translated into structured event and component data compatible with SAPHIRE’s risk modeling framework.
SAPHIRE is developed by the U.S. Nuclear Regulatory Commission (NRC) and the Idaho National Laboratory (INL) for evaluating reliability, availability, and safety of complex engineered systems — including nuclear power plants, SMRs (Small Modular Reactors), and other critical infrastructure.
By linking FRI3D’s 3D fire and hazard simulation environment with SAPHIRE, users can quantitatively assess risk using scenario-based data that includes fire propagation, equipment damage states, and failure probabilities derived from simulation results.
Purpose of Integration#
| Objective | Description |
|---|---|
| Hazard-to-Risk Translation | Convert FRI3D fire, smoke, and thermal simulation results into structured event and component data. |
| Scenario Automation | Automatically generate multiple PRA scenarios based on spatial hazard outcomes (e.g., equipment damaged in different zones). |
| Quantitative Risk Evaluation | Provide SAPHIRE with frequency and consequence data to calculate Core Damage Frequency (CDF), Large Early Release Frequency (LERF), or other metrics. |
| Bidirectional Traceability | Maintain traceability between FRI3D geometry zones and SAPHIRE system components for review and verification. |
Data Mapping Overview#
FRI3D organizes data for SAPHIRE export into logical mappings between spatial zones, equipment models, and failure events.
| FRI3D Entity | SAPHIRE Equivalent | Description |
|---|---|---|
| Zone / Compartment | Location Group / Plant Area | Fire compartment or analysis boundary used to organize event data. |
| Equipment Instance | Basic Event / Component | Individual component or system element with a defined failure probability. |
| Fire Scenario | Initiating Event | Scenario initiating event (e.g., cable tray fire, room fire). |
| Fire Progression Path | Event Sequence / Sequence Logic | Propagation path mapped to SAPHIRE event sequence tree. |
| Simulation Result | Failure Probability / Conditional Probability | Quantitative outcome derived from FRI3D simulation (e.g., damage threshold exceeded). |
| Mitigation System | Recovery Action / Human Reliability Event | Detection or suppression systems represented as recovery events in SAPHIRE. |
Export Workflow#
1. Simulation and Analysis#
- Run fire, smoke, or thermal simulations within FRI3D to determine temperature profiles, smoke spread, and equipment exposure.
- Identify damaged equipment and zone-level hazard propagation.
2. PRA Data Preparation#
- FRI3D’s PRA export module aggregates:
- Equipment metadata (unique IDs, functional class, location)
- Hazard exposure data (temperature/time thresholds, probability of failure)
- Scenario classification (initiator type, duration, boundary conditions)
3. SAPHIRE Data Structuring#
- The data is organized into the following SAPHIRE-compatible elements:
- Initiating Events (IEs)
- Basic Events (BEs)
- Fault Tree (FT) definitions
- Event Trees (ET)
- Sequences and System Models
4. Export Generation#
FRI3D produces structured XML or CSV output for SAPHIRE import.
Supported export formats include:
| File Type | Purpose | Description |
|---|---|---|
saphire_events.xml | Basic Events | Contains event names, probabilities, and identifiers. |
saphire_sequences.xml | Event Sequences | Describes possible fire progression sequences. |
saphire_faulttrees.xml | Fault Trees | Logical component relationships. |
saphire_summary.csv | Summary Table | Simplified scenario overview for batch review. |
5. Import into SAPHIRE#
- The exported XML/CSV files are imported through SAPHIRE’s Model Import Utility.
- Components and event trees can then be connected to the plant model for quantitative risk evaluation.
Example Export Snippets#
XML Example#
CSV Example#
Tagging and Data Requirements#
FRI3D requires proper tagging of components in the model before PRA export.
This ensures a consistent mapping between geometric and logical components.
| Tag | Description | Example |
|---|---|---|
COMPONENT_ID | Unique component identifier linked to SAPHIRE event name. | Pump_A1, Panel_12 |
ZONE_ID | Spatial fire compartment or simulation volume. | Zone_1A, ControlRoom_A |
FUNCTION_CLASS | System-level role or dependency. | CoolingSystem, PowerSupply |
FAILURE_MODE | Type of damage or functional failure. | Overheat, ShortCircuit, LossOfFunction |
⚠️ Note:
Unmapped or untagged components will be excluded from PRA export.
Ensure that component and zone identifiers match those expected in SAPHIRE’s model definition.
Reliability and Limitations#
- Export is aligned with SAPHIRE 8.x XML Schema (tested with NRC/INL releases).
- Bidirectional update (importing PRA results back into FRI3D) is planned but not yet supported.
- Human Reliability Analysis (HRA) events must be defined manually in SAPHIRE.
- Quantitative results depend on simulation accuracy and failure correlation models used during export.
Summary#
- FRI3D exports simulation-based failure and scenario data directly into SAPHIRE-compatible XML and CSV files.
- Enables automated PRA scenario generation from fire and hazard analyses.
- Requires consistent tagging of zones and components for proper mapping.
- Provides a foundation for integrated risk-informed decision-making across simulation and PRA domains.
References#
SAPHIRE User Manual (Version 8.1) — Idaho National Laboratory, U.S. NRC
https://saphire.inl.gov/U.S. NRC NUREG/CR-7039 — SAPHIRE Technical Reference Manual, 2011.
Describes the XML schema and data import structure.FRI3D PRA Export Guide — Internal Technical Note, Centroid LAB, 2025.
Details the mapping between FRI3D zones, equipment, and PRA structures.IEC 61025:2006 — Fault Tree Analysis (FTA) Standard.
Reference for logical dependency modeling used in SAPHIRE.
⚠️ Disclaimer:
SAPHIRE export functionality in FRI3D is intended for interoperability with established PRA tools.
Due to evolving SAPHIRE schema updates and user-defined modeling structures, exported files should be validated in SAPHIRE before quantitative use.