factor of safety

American  

noun

1. the ratio of the maximum stress that a structural part or other piece of material can withstand to the maximum stress estimated for it in the use for which it is designed.

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factor of safety British  

noun

1. Also called: safety factor.  the ratio of the breaking stress of a material or structure to the calculated maximum stress when in use

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Etymology

Origin of factor of safety

First recorded in 1855–60

Example Sentences

See Examples For:

factor of safety

“Metro added a 20% factor of safety to this rate to arrive at a proposed inspection interval of every eight days per wheelset,” she wrote.

From Washington Post ● Nov. 4, 2021

The regulations and factor of safety requirements aren’t as strict because, if it fails, no one is going to die.

From Scientific American ● Jul. 31, 2015

“The factor of safety is now back to being a high criterion when selecting an airline.”

From Time ● Mar. 6, 2015

An addition of .25 is also made to the factor of safety, when the strakes are not entirely under or over.

From Modern Machine-Shop Practice, Volumes I and II by Rose, Joshua

Allowing a generous factor of safety, let us say that a 250 is all sufficient.

From Scientific American Supplement, No. 611, September 17, 1887 by Various