Fault Tree Software - FaultTree+ Version 11

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New Features for FaultTree+ Version 11 can be found here.

Download FaultTree+ Technical Specification

 Integrated Fault and Event Tree Analysis

FaultTree+ is a fully interactive graphics and analysis program for performing probabilistic risk assessment using integrated fault tree, event tree and Markov analyses. The program runs under Microsoft Windows 95/98/2000, NT, Me and XP and is capable of analysing large and complex fault and event trees producing the full minimal cut representation for fault tree TOP events and event tree consequences.

FaultTree+ is used by many organisations as part of their implementation of IEC 61508.

 Fault and Event Tree Construction

• Standard Windows dialogs, menus and controls for easy function access and layout
• Automatic drawing facilities produce high quality diagrams without any effort from the user
• Time saving features such as double mouse clicks to bring up gate, event and branch attributes
• Drag and drop add mode for fast tree construction
• Extensive diagram scale and shift options including manual shifting of sub-trees and automatic alignment to the screen edit area
• Global and local font selection allowing highlighting of labels and descriptions
• Automatic paging facilities - simply identify gates or branches with a new page tag and the program takes care of pagination
• Append facilities for fault trees produced by different users
• OR, AND, VOTE, NOT, Exclusive Or, Inhibit and Priority AND gates supported
• Basic, Conditional, Undeveloped, Dormant and House basic event symbols supported
• Multiple branching supported for event trees
• Multiple consequence categories for event trees
• Primary and secondary event trees
• Extensive on-line help facility including key word search
• Attributes such as event parameters, generic model codes, branch names and column probabilities may be displayed on diagrams if required
• Cut, copy and paste facilities available for fault tree symbols
• Flexible label formatting allows the user to place descriptive text anywhere within a fault or event tree page
• Project database tables may be easily edited using direct and dependency filtering
• Event and gate names may be globally edited
• Circular logic checks during fault tree construction
• Import and export facilities for data models
• Undo and automatic backup facilities
• Delete hidden data facility for tidying-up large projects

 Analysis

FaultTree+ provides CCF analysis, importance analysis, uncertainty and sensitivity analysis facilities. The program allows users to construct a single project database containing generic data and event tables, fault trees with multiple TOP events, event trees originating from different initiating events, CCF tables and consequence tables. Fault and event tree pagination is automatically controlled by the program. Fault tree TOP events may be used to represent specific nodes in the event tree. Multiple branches are also handled to allow for partial failures. FaultTree+ uses efficient minimal cut set generation algorithms to analyse large and complex fault and event trees. NOT logic may be included in the fault and event trees at any level and event success states retained in the analysis results as an option.

• Range of event failure and repair models including fixed rates, dormant, sequential, standby, time at risk, binomial, Poisson and initiator failure models
• Fault tree house event analysis
• Full minimal cut set analysis (including success states if required)
• CCF analysis using the beta factor, MGL, alpha factor or beta BFR methods
• Post-processing facilities for accurate upper bound calculations
• Importance analysis with Fussell-Vesely, Birnbaum, Barlow-Proschan and Sequential importance measures. Risk measures provided for event tree consequences
• Initiator-enabler analysis for sequence dependent analyses
• Uncertainty analyses allowing confidence levels to be determined from event failure and repair data uncertainties
• Sensitivity analysis allowing the automatic variation of event failure and repair data between specified limits
• Time dependent analysis providing intermediate values for time dependent system parameters
• Verification checks providing diagnostic information before commencing an analysis. Checks are made for circular logic, undefined gates, invalid initiators etc.
• Status facility to indicate whether analysis results are out of date with respect to project data

 Reports, Import/Export

FaultTree+ includes the latest version of the report generator and import/export wizard. The report generator provides you with standard reports containing tabular data, graphs or diagrams. You can also customise your own reports in next to no time! You can print out the reports directly or export them to a Rich Text Format file. Many software packages such as Microsoft Word can read RTF files allowing you to include the reports in other documents.

Download FaultTree+ DLL Technical Specification

Users may construct new FaultTree+ project files that may be opened using FaultTree+ V10.1 and later versions. In addition users may edit, or read data from, FaultTree+ project files that have been constructed by the FaultTree+ program itself.

The FaultTree+ DLL may also be used to send messages to the FaultTree+ program whilst it is running on the same machine. The DLL also provides a routine to start up the FaultTree+ program and open an existing project file. Messages may only be sent to FaultTree+ V10.1.2 and later versions if it is licensed to run in fully operational mode. Messages may not be sent to FaultTree+ if it is operating in demonstration mode. One of the primary functions of the message system is to allow external applications to construct and modify fault tree projects and then use FaultTree+ to perform the calculations. Results may then be saved within the FaultTree+ project file and read into the external application.

Users may therefore build up applications to:

• Automatically construct fault trees from design models stored in other applications
• Automatically manipulate failure data and perform special global edit operations
• Provide a high level interface to manipulate fault tree data and assess the effects of changes (Living PSA)
• Develop operational risk monitors
• Provide special graphical data input and data display capabilities