Fail-safe

<p>In <a href="/facts/Engineering/RFVg8H3I">engineering</a>, a fail-safe is a design feature or practice that, in the event of a <a href="/facts/Failure_causes/4Ue191js">failure</a> of the design feature, inherently responds in a way that will cause minimal or no harm to other equipment, to the environment or to people. Unlike <a href="/facts/Inherent_safety/NVp3Jq2q">inherent safety</a> to a particular hazard, a system being "fail-safe" does not mean that failure is naturally inconsequential, but rather that the system's design prevents or mitigates unsafe consequences of the system's failure. If and when a "fail-safe" system fails, it remains at least as safe as it was before the failure. Since many types of failure are possible, <a href="/facts/Failure_mode_and_effects_analysis/fdjxbXxP">failure mode and effects analysis</a> is used to examine failure situations and recommend safety design and procedures.
</p><p>Some systems can never be made fail-safe, as continuous availability is needed. <a href="/facts/Redundancy_(engineering)/odqzTmIo">Redundancy</a>, <a href="/facts/Fault_tolerance/rasrYlJk">fault tolerance</a>, or <a href="/facts/Contingency_plan/SlyNus3m">contingency plans</a> are used for these situations (e.g. multiple independently controlled and fuel-fed engines).
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Fail-safe open-in-new

Fail-safe