Fehlereignis

Fehlereignis is a term used in German-language reliability, safety and risk analysis to denote an event in which a component, subsystem, or system fails to perform its intended function. It represents a deviation from normal or required performance and can reflect hardware faults, software malfunctions, or human errors. In practice, Fehlereignis is often treated as a base or occurring event in methodological frameworks such as fault tree analysis (FTA) and failure mode and effects analysis (FMEA).

Classification and usage

Fehlereignisse can be categorized by their origin, for example hardware Fehlereignis, software Fehlereignis, human Fehlereignis or environmental/stress-related Fehlereignis. They are used as generating events in fault trees and as failure modes in risk assessments. The term emphasizes the occurrence of a fault rather than the definitive cause, which is typically identified in subsequent analysis such as root cause investigation.

Relation to other terms

Fehlereignis is distinct from related concepts. An Ausfall (failure) often implies a complete loss of function, while a Defekt (defect) points to a faulty condition at a component level. A Störung (disturbance) may describe abnormal operation that does not necessarily constitute a full Fehlereignis. In safety standards and engineering practice, Fehlereignisse are identified, documented, and mitigated to support reliability growth and risk reduction.

Context and industry use

The concept is used across industries including automotive, aerospace, energy, and process safety. Properly identifying Fehlereignisse supports systematic risk assessment, design of mitigations, and evidence for safety cases or reliability demonstrations.