FTA Studio vs SAPHIRE
SAPHIRE (Systems Analysis Programs for Hands-on Integrated Reliability Evaluations) is the U.S. Nuclear Regulatory Commission's PRA tool, developed and maintained by Idaho National Laboratory. It's free for U.S. government use and used in essentially every Level-1 PRA for the U.S. nuclear fleet. FTA Studio is a different shape — browser-based, broader-industry IEC 61025 fault-tree analysis, free Community / $99 Enterprise. Here's where each one fits.
At a glance
| FTA Studio | SAPHIRE | |
|---|---|---|
| Vendor | FTA Studio (independent) | Idaho National Laboratory / U.S. NRC |
| Deployment | Browser, no install | Windows desktop install |
| Pricing | $0 Community / $99 seat/yr | Free for U.S. government / licensee use; export-controlled |
| Open access | Open registration, anyone can use | Distribution gated; eligibility verification required |
| OS | Any (browser) | Windows only |
| Primary domain | Cross-industry (auto, aero, rail, medical, oil & gas, nuclear) | Nuclear PRA (Level-1, Level-2) |
| Fault Tree Analysis | ✓ IEC 61025 | ✓ NUREG-0492-aligned |
| Event Tree Analysis | ✓ Enterprise | ✓ deeply integrated (sequence-level) |
| End-state binning | — | ✓ Level-1 / Level-2 PRA workflow |
| Markov / Bayesian uncertainty propagation | ~ Monte Carlo (Enterprise) | ✓ integrated |
| Common-cause failure | ✓ Beta, MGL | ✓ Alpha-factor and others |
| Generic plant data | — | ✓ integrated NUREG/CR data sources |
| Approval / audit workflow | ✓ Enterprise | — external to tool |
| Industry templates | 8 cross-industry, free | Plant-specific PRA models (licensee submissions) |
The honest differences
When to pick FTA Studio
- You're not in the U.S. nuclear fleet. SAPHIRE's distribution is restricted; FTA Studio is open to anyone.
- Your problem is FTA, not Level-1 PRA. Standalone fault trees, FMEA, ETA, importance ranking — without the full PRA event-sequence machinery.
- Cross-industry work. Automotive, aerospace, rail, medical, oil & gas — SAPHIRE is purpose-built for nuclear; FTA Studio targets all of them with worked templates.
- Cross-platform. macOS, Linux, ChromeOS — none of which run SAPHIRE.
- Modern UX expectations. SAPHIRE is a powerful tool with an interface that reflects its 1980s lineage. FTA Studio is browser-native.
When to pick SAPHIRE
- You're submitting a PRA to the NRC. SAPHIRE is the de-facto reference; switching to a different tool for a Level-1 PRA submission is a non-trivial regulatory conversation.
- Full integrated PRA — initiating events, accident sequences, end-state binning, Bayesian update from operating experience. FTA Studio doesn't (and won't) try to be a Level-1 PRA tool.
- You need the integrated NUREG-data libraries (CCF parameters, generic component reliability data, plant-specific adjustments).
- Eligibility cost is zero. If you qualify for free SAPHIRE access, that's hard to beat.
Where the two tools complement, not compete
Many nuclear-industry users we've talked to use SAPHIRE for the full PRA submission workflow, and reach for a lighter tool for early-phase work — exploratory FTA during design, supplier audits, training new staff, or building diagrams for non-PRA reports. That's a use case FTA Studio fits well: open the browser, build the tree, export an IEC JSON or PDF, done.
For non-nuclear safety-critical industries — automotive ISO 26262, aerospace ARP 4761, rail EN 50126, process IEC 61511 — FTA Studio is built for the actual workflows those standards expect, and SAPHIRE's PRA-specific machinery is mostly off-target.
SAPHIRE is developed and maintained by Idaho National Laboratory under contract to the U.S. Nuclear Regulatory Commission. Not affiliated. Eligibility and distribution terms may change — consult INL directly.