Bowtie diagrams were developed in the 1970s as a way of illustrating how risks are managed.  Their use increased significantly after the Piper Alpha disaster and continues to this day.  Although originating in the process industry, other sectors are starting to use Bowtie diagrams.

However, the popularity of Bowtie diagrams is not without its problems.  There has been no definitive guide or standard on how to develop them, or even when they should be used.  People clearly like Bowtie diagrams, but often have inflated opinions of what they can actually achieve and there is a misguided assumption that they can be applied to any activity where there is risk.  Representation of human factors is one particular area where there appears to be a lot of variability and differences of opinion. 

I have written this paper to share my views of how Bowtie diagrams should be used and how human factors should be represented.  I hoped it would start some discussion.  If you have any comments, I would be very happy to receive them.

Bowtie diagrams and human factors (full paper in PDF format)