# Factor of Safety

Written by Jerry Ratzlaff on . Posted in Dimensionless Numbers

Factor of safety, abbreviated as FS, also called safety factor, a dimensionless number, is the ability of a system's structural capacity to be usable beyond it's expected or acrual loads.

## factor of safety formula

 $$\large{ FS = \frac {UTS}{R} }$$

Where:

$$\large{ FS }$$ = factor of safety

$$\large{ R }$$ = applied stress

$$\large{ UTS }$$ = ultimate tensile stress