Definition

Semantics

The term error is ambiguous. The meaning of the term is subjective; it depends on the on the expectations of the person using it about the execution of the other stakeholders. Typical expectations about the other stakeholders are:

• The operators expect that the system behavior will fit their intentions
• The designers expect that the operators will behave according to the designer's intentions
• The stakeholders expect that the system productivity is optimized and that the costs of incidences are minimized.

The value of an error

An error may be significant or minor, depending on the gap between the expectations and the execution.

Operator's error

There are many ways to define errors. The traditional ways associate the error with the operator 's activity, which either triggered an incidence or failed to prevent it. Following Hollnagel (1983) 

• An operator's error is a subset of the the operator 's activity preceding a costly incidence, which justifies and subsequently invokes investigation.

This definition assumes that the operators could hypothetically act to prevent the incidence, but actually they acted differently (Dekker, 2007 ).

Related topic

Updated on 03 Mar 2017.