Margin of safety and Safety factor

Margin of safety noun - The margin required in order to insure safety.

Safety factor and margin of safety are semantically related. In some cases you can use "Safety factor" instead a noun phrase "Margin of safety".

Safety factor noun - The ratio of the breaking stress of a structure to the estimated maximum stress in ordinary use.

Margin of safety and safety factor are semantically related. You can use "Margin of safety" instead a noun phrase "Safety factor".