RiskSpectrum PSA

The most widely spread PSA tool in the world

RiskSpectrum PSA is a creative software that you can use to edit, debug, test and deploy a fault tree and event tree model. In addition to what most standard fault tree and event tree editor provide, RiskSpectrum PSA includes tools for model completion, MCS tracing, scripting based updating, and many more features to enhance the PSA model development and maintenance process.

Via its intuitive user interface, you can model everything from the basic fault tree with AND and OR gates, right through to advanced fault tree and event tree integration of sequences in linked event trees with boundary conditions and CCF events.

The integrated RiskSpectrum Analysis Tool (RSAT) is specially designed for solving  very large Fault Tree & Event Tree models. It offers MCS (Minimal Cut Set), BDD, sensitivity, importance, uncertainty and time-dependent analysis.

There are also two add-on tools for RiskSpectrum PSA:

  • RiskSpectrum PSA Macro for simplifying model update
  • RiskSpectrum I&AB for calculation of repairable equipment unavailability. 


Software In Action


Fault Tree Editor

Build and maintain your fault trees in the user-friendly graphical user interface in the RiskSpectrum PSA fault tree editor.

Open multiple fault tree editor, drag-and-drop objects, copy and paste events and branches, link fault trees using transfers, etc. 

Event Tree Editor

RiskSpectrum PSA offers an event tree editor with advanced features developed over the many years of use.

Function Events (Top Events) and their bransch points are easily added. The Function Events input are defined with links to top gates in the fault trees or simply Basic Events.

Boundary Conditions can be applied downstream from Function Events, or for all sequences by adding them to the Initiating Event. Event Tree sequences can be linked to other Event Trees to enable separate modelling of sequence groups.  



RiskSpectrum Analysis Tool

RiskSpectrum Analysis Tool (RSAT) is renowned for its ability to solve very large and complex Fault Tree and Event Tree models. It converts the fault tree and event tree logical structures to a Minimal Cut Set (MCS) list and quantifies the top frequency or probability, sensitivity, importance and time dependent analysis. Uncertainty analysis is quantified using the built-in Monte Carlo simulation tool. 

RSAT also includes an algorithm for converting the MCS to a Binary Decision Diagram (BDD) for exact quantification of  top event frequencies or probablity, importance, sensitivity and uncertainty.  

RiskSpectrum CutsetTracer

RiskSpectrum CutsetTracer is a tool that presents you with the possible paths that a a selected MCS can propagate to fail the top event. 

  • Function Events and Event trees involved are shown at the top
  • Green FEs are not failed – Red failed
  • The Fault Tree hierarchy shows which events are true (blue) due to the chosen MCS 
  • Red Events are true due to boundary conditions
  • Exchanges made are indicated with an E in a circle
  • Information about selected events is shown in the right part of the window.

RiskSpectrum ModelCompare

Assess and illustrates in colour what has been added, changed or removed between two models.

Comparisons between:

  • actual values
  • References
  • Does not search for edit dates

RiskSpectrum HazardLite

RiskSpectrum HazardLite is a tool that facilitates modelling of Hazard events in RiskSpectrum PSA, e.g. earthquake, tsunami, etc.

The frequencies of exceedance based on hazard curves collected from the site can be calculated and equipment fragilities are defined using the three parameters Am, bU and bR

The built-in Monte Carlo simulator is then used for generating hazard event frequencies and fragility probabilities for equipment that can be exported to the fault tree and event tree model in RiskSpectrum PSA.