Safety Factor

What is a Safety Factor

Definition of Safety Factor in Construction

The term safety factor relates to the additional amount of structural strength or durability that is constructed into an assembly. For example the safety factor on a bridge span might be a safety factor of 2.5, which indicates that the bridge span is actually designed to withstand forces and stressed 2.5 times the actual loading forces anticipated. Structural engineers will design assemblies with a safety factor that they feel is appropriate as well as follows all codes and regulations when designing their assemblies. There is a fine balance between the safety factor of a building, bridge, tunnel, etc. and the economy of construction. The higher the safety factor, normally, the more expensive is the construction process. A higher safety factor in most situations includes additional material as well as labor, therefore increasing the cost of the assembly. Developers and owners will try to balance the required and suggested safety factors with the economic impact of the structural design on the budget. The term safety factor is also used to identify the strength of various construction materials, the ability of hangers and attachment assemblies to sustain loads, as well as total building performance, in terms of earthquake and hurricane performance. Safety factor is a very common term within the construction industry and its interpretation and meaning must be clearly understood by all parties to properly manage and supervise the construction process.