Re: [SystemSafety] Root Cause Analysis

From: Steve Tockey < >
Date: Wed, 13 Feb 2013 00:09:53 +0000

Apologies for the delayed reply, I've been buried in other work for the past couple of weeks.

I'm not sure you included it, but I have gotten some mileage out of "Cause Maps" (see the book "Apollo Root Cause Analysis" 3rd Ed, by Dean L. Gano, Appollonian Publications, 2007). See also for some real-world examples of Cause Maps in action. Here's a short description of Cause Maps:

A Cause Map is a structured map of "cause --> effect" relationships that includes the identified problem that is chained forward into negative effects on organizational goals and chained backwards into driving causes. Unlike tools such as Ishikawa (or "fishbone") diagrams, Cause Maps demand clear evidence of the occurrence of the cause(s) and the causality of the effect(s)

I've also heard of, but not used "Bayesian Inference" (Statistical inference from evidence or observation is used to infer or update probability that some hypothesis may be true)


-----Original Message-----
From: Peter Bernard Ladkin <ladkin_at_xxxxxx Date: Tuesday, February 5, 2013 6:16 AM
To: "systemsafety_at_xxxxxx <systemsafety_at_xxxxxx Subject: [SystemSafety] Root Cause Analysis

I have been involved in the IEC standardisation project for Root Cause Analysis, being undertaken by
TC56 WG3 (the project team designation is PT3.23) for those who want to look it up on

I wrote some material, including
* a set of terms and definitions compatible as far as possible with the
Electrotechnical Vocabulary (IEV, at , also IEC 60050)
* short descriptions (2-3pp) of four methods, Accimaps, MES, SOL and WBA,
along with comments on
strengths and limitations

It appears at time of writing that this material will not be used. I think it could be useful to
others, so I put it all together on a paper on the RVS WWW site.

I just wrote a blog post at which references the paper, and also includes a list of what I think are the currently most-useful
methods in industrial use for root cause analysis for accidents and significant individual
incidents. (I distinguish this from root cause analysis for quality control, in which methods such
as "5 Why's" are thought to be helpful and Fishbone Diagrams are thought of as sophisticated; both
are useless for the analysis of complex individual incidents. Some methods such as WBA are used for

I'd be grateful for pointers to methods I have omitted. I would be even more grateful if people
would like to write short synopses in the form used in the paper for some of these methods! Then we
can put all the contributions on the WWW for people to read.


Prof. Peter Bernard Ladkin, Faculty of Technology, University of
Bielefeld, 33594 Bielefeld, Germany
Tel+msg +49 (0)521 880 7319

The System Safety Mailing List

The System Safety Mailing List
Received on Wed Feb 13 2013 - 01:10:04 CET

This archive was generated by hypermail 2.3.0 : Tue Jun 04 2019 - 21:17:05 CEST