Recommended Fault Tree Software & Vendors

There are five fault tree software packages that fault-tree.net can recommend

We do not endorse any single package over another.  Read the Fine Print

No vendor has paid for our endorsement, or paid to be included on this page

Data Systems & Solutions

USA Telephone:  703 . 375 . 2800
Fax:  1 . 703 . 375 . 2959
Website:   http://www.ds-s.com

Data Systems and Solutions
12100 Sunset Hills Rd, Suite 310
Reston, Virginia, 20190

Fault Tree+
Isograph Inc. (USA & Canada)

USA Telephone: 949 . 502 . 5689
FAX:  949 . 502 . 5933

E-mail:      sales@isograph.com 
Isograph Inc.
8001 Irvine Center Drive
Suite 1430 
Irvine, CA  92618
Isograph Ltd
(For Europe and Rest of the World)
Sales :     +44 1925 43 7001
Support : +44 1925 43 7002
Fax : +44 1925 437010
E-mail :

Item Tool Kit
Item Software (USA) Inc.

USA Telephone: 714 . 935 . 2900
FAX: 714 . 935 . 2911

E-mail:       sales@itemsoft.com


Item Software (USA) Inc.
(USA, Canada, Central & S. America)

2190 Towne Centre Place,
Suite 314
Anaheim, CA, 92806 USA
Phone: 714-935-2900
Fax: 714-935-2911
URL:    www.itemsoft.com
E-Mail: sales@itemsoft.com

Item Software Inc.
(Europe & Rest of The World)
1 Manor Court,
Barnes Wallies Road,

Fareham, Hampshire, PO15TH,UK
Phone: +44(0) 1 489 885085
Fax:: +44(0) 1 489 885065
E-Mail: sales@itemuk.com

Relex Fault Tree /
Event Tree

Relex Software Corporation

USA Telephone:  724 . 836 . 8800
FAX:  724 . 836 . 8844

E-mail:     info@relexsoftware.com  
Website:  http://relexsoftware.com 

Relex Software Corporation
540 Pellis Road
Greensburg, PA 15601



Telephone:  + 46 8 445 21 00  
        Sales:  + 46 8 445 21 20
    Support:   + 46 8 445 21 10
FAX:  + 46 8 445 21 01

Box 1288
S-172 25 Sundbyberg

Each software package and vendor has particular strengths in capability, customer support, updates, features and useability: 

  • All are excellent packages. 
  • Each package is user-friendly and has an excellent Graphical User Interface.  This is very important: 
    • The fastest algorythm in the world will not do you any good if it takes you forever to build a basic tree and enter the reliability data.
    • Frustration due to a bad GUI takes away from concentrating on developing the logic and analyzing the system.
    • A good GUI can even allow you to get fault trees done quickly for management presentations.  It won't get you a date, but it can impress the boss.  Management loves pretty pictures done fast.
  • Several of the programs include an Event Tree Development and Analysis module as part of the base price.  If you perform analyses in which you link fault trees with event trees, (such as Probabilistic Risk Assessments) getting Event Tree Analysis in the base price of the software can be a bargain.
  • Some packages can support Markov analysis.
  • Some packages Offer Binary Decision Diagram for calculating cutsets for enormous trees. 
  • Several of the vendors offer integrated packages or toolkits which can link into reliability databases, create FMEAs which can in turn be linked into fault trees, event trees, reliability block diagrams  and other relaibility/safety analyses. 
  • We recommend you check out several of them before deciding which one to purchase. 

These programs are all expensive - and they are all worth every penny.  I am not being hyperbolic when I say,that any one of them can easily save tens-of-thousands of dollars in engineering time, if you regularly perform large fault tree analyses on complex systems (even for one or two analysts).


The Fine Print

  • Aren't we being a bit coy when we refuse to recommend a particular package over another?  
    • To understand my point, ask yourself this,  "Which car manufacturer out of BMW, Volvo, Porsche, or Lexus, makes the absolute best car? " . . . For everyone? . . . Under all circumstances?
      • Try driving your mother-in-law around in the back of a Porsche Boxster. 
      • Yet, try and take a Boxster away from someone who owns one!
  • You may be asking yourself, "Is Item Software on the recommended list because they provide financial support?"  That is a Very Fair Question.   
    • The answer is . . .  Yes and No . . . The truth is, we would never have approached Item Software and accepted their kind financial support if we did not did not feel confortable in recommending their software in the first place. (It's a "chicken and egg" kind of  thing)
    • And . . . you should all be made aware that it was Item Software who suggested putting  together a page of all the fault tree software vendors (of our choice) as a service to the System Safety and Reliability Communities.
    • Item Software DID NOT suggest who should be included as recommended vendors.  Nor, did they have have any input to this page whatsoever (other than suggesting it in the first place).
    • We are not endorsing Item Software over any other vendor. You should check out all of these packages to see which one is right for your needs. 
  • fault-tree.net has received absolutely no compensation for recommending these vendors.  This includes, direct contributions or payments, web click-through or advertising fees.  Nor, do we have any arrangement for making commissions from any of these vendors  as a result of any sales arising from our recommendation.
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