| The incident pit and redundancy
This post is motivated by posts (pasted below) in the thread 'what do you regard as wrong'.
My understanding is that the incident pit is the phenomenon that failures (equpiment failure, loss of kit, separation, etc) tend to increase the likelihood and negative consequence of subsequent failure. Failures make failures more likely and their consequences more serious. This combination of increased likelihood of failure and increased consequence of a failure creates increased risk.
I assume that the increased likelihood of a subsequent failure occurs due to increased stress and task loading caused by the previous failure(s). And that the increased negative consequence of a subsequent failure can result from loss of redundancy caused by the previous failure(s).
For example, separation may increase stress, increase task loading, impair good judgement, and make a second failure more likely. It would also result in zero redundancy if one's only source of redundancy is the team. This reduction in redundancy increases the potential negative consequence of a subsequent failure.
As Mark writes, many of the fatalities in the BS-AC incident reports may be attributed to this phenomenon. It is something we should guard against.
If my representation of the incident pit is correct, what should we do?
My impression (gained from BS-AC and GUE training) is that it suggests that we should be concerned primarily with making an appropriate response to failures. We should aim to respond in a way that gets us out of the pit, or at least stops us descending further into it. Training that includes simulated failures and encourages reasoned and relaxed responses to failures could be one approach to this aim.
I'm less certain of what the incident pit phenomenon means we should do regarding redundancy (i.e., the number of failures we cater for). My understanding of Mark's post is that he thinks it means we should increase our level of redundancy. He might, however, have been only suggesting we cater for separation plus one other failure (which I agree is prudent if its known that a dive involves significant likelihood of separation).
I'm interested in knowing what people think the incident pit phenomenon suggests about the level of redundancy we carry.
Owen
(rjack)
Most of these come down to having 2+ major failuers on 1 dive. [snip]
(Mark Chase)
Look at the BSAC incident report on fatalities. Many fatalities started out with seporation and then a second incident occured causing the fatality.
This is repeated over and over again in the reports.
They call it the incident pit.
ATB
Mark Chase |