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

That substructures and retaining walls designed according to the Rankine or similar theories have an additional factor of safety from too generous an assumption in regard to earth pressure is practically admitted everywhere.

From Pressure, Resistance, and Stability of Earth American Society of Civil Engineers: Transactions, Paper No. 1174, Volume LXX, December 1910 by Meem, J. C.

This is the line that gives a sound factor of safety.

From The Plattsburg Manual A Handbook for Military Training by Ellis, Olin Oglesby