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Steven Shorrock @StevenShorrock
, 14 tweets, 5 min read Read on Twitter
A few concepts for the curious in system safety:
Interaction
Local rationality
Trade-offs & compromises
Patterns
Work-as-imagined, -prescribed, -done, -disclosed
Adaptation & adjustment
Drift
First & second stories
Field expertise
Emergence
Equivalence
A tweet on each of the above follows with a link to something fairly accessible that might be of interest.
Interaction:
More interesting than humans, environments, equipment, procedures, regulations, etc is the interaction that occurs between them, at micro, mesa and macro levels, and how these create influence and flows of information and activity. skybrary.aero/index.php/Tool…
Local rationality:
People do things that make sense to them given their goals, understanding of the situation and focus of attention at that time. Activity needs to be understood from the local perspectives of those doing the activity and affected by it.
skybrary.aero/index.php/Tool…
Trade-offs and compromises:
We make trade-offs and compromises to resolve goal conflicts and to cope with complexity and the uncertainty. Key trade offs include those between efficiency and thoroughness and acute and chronic goals. skybrary.aero/index.php/Tool…
Patterns:
Work-as-done tends to form patterns of activity, which change in response to new demands, constraints, resources, incentives. These can be studied, modeled, discussed, but we tend not to ‘see’ them as they are so ordinary...from the inside. [One use of the term.]
Work-as-imagined, -prescribed, -done, -disclosed:
What people imagine they/others do, what people ‘should’ do, what people do, and what people say they do are not the same thing. We need to understand areas of overlap and divergence.
humanisticsystems.com/2016/12/05/the…
People continually adjust and adapt to cope with variability in demands and conditions. Mostly, this is what ensures that things work, but sometimes adjustments and adaptation is unwanted in light of the system’s need and tolerance for variability
skybrary.aero/index.php/Tool…
Drift:
Over time, conditions and behaviour (individual, group, organisational) can drift into an unwanted state. This can be difficult to see from the inside, especially attention is paid only to incidents (relatively infrequent) and not normal work.
First and second stories:
First and second stories differ in time to emerge, the time period considered (before, during, after accident), degree of personalisation, focus on components vs interactions, context and complexity, newsworthiness. c.ymcdn.com/sites/www.npsf…
Field expertise:
The people who do the work and are affected by it are the specialists in their work and are critical for system improvement. To understand work-as-done and improve how things really work, recognise and integrate field expertise. skybrary.aero/index.php/Tool…
Emergence:
System behaviour in complex systems is often emergent; it cannot be reduced to the behaviour of components and is often not as expected. Context, cascades and patterns, must be uncovered, modeled and discussed.
skybrary.aero/index.php/Tool…
Equivalence:
Success and failure come from the same source – ordinary work. Understanding safety only with reference to failures ignores the conditions and behaviour that also create success, and interventions may well have unintended consequences.
skybrary.aero/index.php/Tool…
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