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

They're often in their own corridors with really, really high factors of safety in how those corridors are designed.

From Salon

Early on, Ogden ruled that what he termed “the factor of safety” in both the tank’s construction and its inspection had been almost nonexistent and those elements had caused the disaster.

From Literature

The mine’s tailings storage has been more conservatively designed, Northern Dynasty said, with enhanced buttresses, greater slope angles and an improved factor of safety.

From Reuters

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

From Scientific American

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

From Time