Glossary of Data Variables for Fatal and accident causation ... - ERSO

Manual For SafetyNet accident causation system (SNACS)
This is not the case here however, because there are both general and specific
genotypes which link to the chosen consequent. Instead we have rule nr 4,
which says:
4 If none of the available genotypes for the chosen consequent is relevant,
given the information available about the accident, the analysis stops.
This rule applies to our case, because none of the genotypes available are
relevant for the description of Kalle’s accident. This means that we settle for the
general genotype “Fatigue” (E3) as the end point of the analysis describing that
Kalle was rather tired.
Now that we have systematically described all the reasons that we know about
which have contributed to the accident, we put it all together into a single
SNACS description looking like this:
Genotype: Internal
competing activity (E3.3)
Explanation: Kalle’s cell
phone is ringing and he
is checking who is
calling
Genotypes: reasons for the
dysfunctional behaviour
Genotype:
Distraction (E3)
Explanation: Kalle
has his mind on
something else
Genotype: Fatigue
Explanation: Kalle
didn’t sleep well
last night
Genotype: Missed
observation (B1)
Explanation:
Kalle doesn’t see
that the traffic light
has turned red
Phenotype:
dysfunctional
behaviour
from physics
standpoint
Phenotype:
Timing: No
action (A1.3)
Explanation:
The vehicle
does not stop
when the traffic
light turns red
Accident
Figure 15: Final SNACS analysis of Kalle's accident
Because the choice of phenotypes and genotypes always will include an
element of subjective judgement, it is very important that the motivation for
choosing a certain genotype or phenotype is made transparent. You should
always write a couple of lines explaining why you choose a particular
phenotype/genotype, so that anyone else who reads the analysis can follow
your thinking and start an informed discussion if there is disagreement.
6.6.3 Multiple chains of analysis
What we do with the genotype linking is to systematically describe all the chains
of events that led to the phenotype, and each chain is a series of linked
genotypes with a phenotype in the far end. This means that in the analysis
above, there are really two separate chains of contributing factors, which
look like this:
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