The Myths of Human Error


Humans always have, and always will, make errors. Yet this is not an article about human error as much as it is about the most common myths surrounding human error. For the sake of this article we will define an error as “something you didn’t intend to do.”

The first myth is that if you are not experiencing unwanted outcomes (such as incidents, accidents, etc.) then no errors are occurring. Yet errors are inevitable; either employees are not reporting them, or they have developed work-arounds. Eventually, the errors will occur at the most inopportune time and you will experience an unwanted outcome. As a result, these events may seem to come out of nowhere. But we now know they are predictable long before they occur. One way to help predict error rates is to note when error precursors are present (see table).

The presence of error precursors like these may help predict error rates.

Another myth is that training, changing procedures, or behavior modifications (i.e., “fixing the worker”) will eliminate our human error issues. Most companies’ investigation processes are traditional fact-based processes, which only communicate what happened, but not why it happened. Context is required to understand the “why.”

Once the context is determined, the use of the traditional corrective actions (the “fix the worker” approach) will diminish dramatically. It will soon become apparent that most of the influences on human error come from organizationally-controlled processes—for example, procedures, tools, or communication.

Organizational weaknesses are defined as “hidden deficiencies in the organization’s systems, processes, procedures, etc., that lie dormant for some period of time causing no apparent harm until initiated by human action.” For example, a company procedure may have a wrong valve number referenced. That procedure is causing no harm until used by an employee who follows the procedure verbatim—and unknowingly turns the wrong valve. This is an example of when the employee’s error (turning the wrong valve) was the result of an organizational weakness put in place by the procedure writer, not the result of the employee’s actions.

Human Performance Improvement (HPI) is a science that studies the causation of human error and the role organizational weaknesses play. The intent of HPI is not to downplay or diminish the employee’s accountability for his or her own actions. But HPI does amplify the way organizational weaknesses influence the human errors that result in accidents and/or incidents.

The US Department of Energy (DOE) has produced two HPI reference manuals that address this whole concept. Both are free to the public. Simply type “DOE HPI Manuals” into an internet search engine to find both publications: DOE Standard Human Performance Improvement Manual Volume 1, “Concepts and Principles”; and DOE Standard Volume 2, “Human Performance Tools for Individuals, Work Teams, and Management.” Or, they can be found and downloaded at

T. Shane Bush, CPT, is co-founder of BushCo HPI, Inc. The firm’s primary mission is to assist companies in eliminating unwanted outcomes related to human error through the implementation of Human Performance Improvement (HPI). Mr. Bush recently presented on HPI at the Pulp & Paper Association’s (PPSA) 76th Annual Safety Conference in San Antonio, TX.