Human error is an action that has been done but that was "not intended by the actor; not desired by a set of rules or an external observer; or that led the task or system outside its acceptable limits".[1] Human error has been cited as a primary cause contributing factor in disasters and accidents in industries as diverse as
nuclear power (e.g., the
Three Mile Island accident),
aviation,
space exploration (e.g., the
Space Shuttle Challenger disaster and
Space Shuttle Columbia disaster), and
medicine. Prevention of human error is generally seen as a major contributor to
reliability and
safety of (complex) systems. Human error is one of the many contributing causes of
risk events.
Definition
Human error refers to something having been done that was "not intended by the actor; not desired by a set of rules or an external observer; or that led the task or system outside its acceptable limits".[1] In short, it is a deviation from intention, expectation or desirability.[1] Logically, human actions can fail to achieve their goal in two different ways: the actions can go as planned, but the plan can be inadequate (leading to mistakes); or, the plan can be satisfactory, but the performance can be deficient (leading to
slips and
lapses).[2][3] However, a mere failure is not an error if there had been no plan to accomplish something in particular.[1]
Performance
Human error and performance are two sides of the same coin: "human error" mechanisms are the same as "human performance" mechanisms; performance later categorized as 'error' is done so in hindsight:[3][4] therefore actions later termed "human error" are actually part of the ordinary spectrum of human behaviour. The study of
absent-mindedness in everyday life provides ample documentation and categorization of such aspects of behavior. While human error is firmly entrenched in the classical approaches to accident investigation and risk assessment, it has no role in newer approaches such as
resilience engineering.[5]
Categories
There are many ways to categorize human error:[6][7]
exogenous versus
endogenous error (i.e., originating outside versus inside the individual)[8]
situation assessment versus response planning[9] and related distinctions in
'slips' occurring when the physical action fails to achieve the immediate objective
'lapses' involve a failure of one's memory or recall
active error - observable, physical action that changes equipment, system, or facility state, resulting in immediate undesired consequences
latent human error resulting in hidden organization-related weaknesses or equipment flaws that lie dormant; such errors can go unnoticed at the time they occur, having no immediate apparent outcome
equipment dependency error – lack of vigilance due to the assumption that hardware controls or physical safety devices will always work
team error – lack of vigilance created by the social (interpersonal) interaction between two or more people working together
personal dependencies error – unsafe attitudes and traps of human nature leading to complacency and overconfidence
Sources
The
cognitive study of human error is a very active research field, including work related to limits of
memory and
attention and also to
decision making strategies such as the
availability heuristic and other
cognitive biases. Such heuristics and biases are strategies that are useful and often correct, but can lead to systematic patterns of error.
Misunderstandings as a topic in human communication have been studied in
conversation analysis, such as the examination of violations of the
cooperative principle and Gricean maxims.
Organizational studies of error or dysfunction have included studies of
safety culture. One technique for analyzing complex systems failure that incorporates organizational analysis is management oversight risk tree analysis.[13][14][15]
Controversies
Some researchers have argued that the dichotomy of human actions as "correct" or "incorrect" is a harmful
oversimplification of a
complex phenomenon.[16][17] A focus on the variability of human performance and how human operators (and organizations) can manage that variability may be a more fruitful approach. Newer approaches, such as resilience engineering mentioned above, highlight the positive roles that humans can play in complex systems. In resilience engineering, successes (things that go right) and failures (things that go wrong) are seen as having the same basis, namely human performance variability. A specific account of that is the
efficiency–thoroughness trade-off principle,[18] which can be found on all levels of human activity, in individual as well as collective.
^Hollnagel, E. and Amalberti, R. (2001). The Emperor's New Clothes, or whatever happened to "human error"? Invited keynote presentation at 4th International Workshop on Human Error, Safety and System Development.. Linköping, June 11–12, 2001.
^Hollnagel, Erik (2009). The ETTO principle : efficiency-thoroughness trade-off : why things that go right sometimes go wrong. Farnham, England Burlington, VT: Ashgate.
ISBN978-0-7546-7678-2.
OCLC432428967.