posted on 2025-07-31, 19:30authored byJH Powell, MJ Hammond, AS Chen, N Mustafee
Current approaches to risk management place insufficient emphasis on the system
knowledge available to the assessor, particularly in respect of the dynamic behaviour of
the system under threat, the role of human agents and the knowledge availability to
those agents.
In this paper, we address the second of these issues. We are concerned with a class of
systems containing human agents playing a variety of roles as significant system
elements - as decision makers, cognitive agents or implementers. i.e. Human Activity
Systems (Checkland, 1999). Within this family of HASs we focus upon safety and
mission critical systems, referring to this sub-class as critical human activity systems or
CHASs.
Identification of the role and contribution of these human elements to a system is a nontrivial
problem whether in an engineering context, or, as is the case here, in a wider
social and public context. Frequently they are treated as standing apart from the system
in design or policy terms. Regardless of the process of policy definition followed,
analysis of the risk and threats to such a CHAS requires a holistic approach, since the
effect of undesirable, uninformed or erroneous actions on the part of the human
elements is both potentially significant to the system output and inextricably bound
together with the non-human elements of the system.
We present a procedure for identifying the potential threats and risks emerging from
the role(s) and activity of those human agents, using the 2014 flooding in SW England
and the Thames Valley as a contemporary example.
Funding
The project was partially supported the EU-CIRCLE (A pan-European framework for
strengthening critical infrastructure resilience) project, funded by the European Union’s
Horizon 2020 research and innovation programme (Grant Agreement No 653824).