What is the formula for calculating the Factor of Safety?

The correct approach to calculating the Factor of Safety (FoS) involves understanding the relationship between the allowable load or stress and the actual load or stress that a component can withstand. The Formula for Factor of Safety is given by dividing the allowable load by the actual load.

When determining the safety factor, we aim to ensure that the structure or material can sustain the expected loads with a significant margin. The allowable value represents the maximum load or stress that a material can safely handle, whereas the actual value reflects the load being applied to it in practice. By using the formula Allowable / Actual, you obtain a dimensionless ratio that provides a measure of how many times stronger the material is compared to what is currently applied.

In this context, if the allowable stress is greater than the actual stress, the Factor of Safety will be greater than 1, indicating a safe design. If the actual stress approaches or exceeds the allowable stress, the FoS drops towards 1 or below, which signifies a potential failure condition.