Axial stress acts in the axis of members, such as columns. Axial tension is common in rods and cables; wile axial compression is common in walls and columns. The following examples illustrates axial design and analysis. Analysis determines if an element is ok; design defines the required size. The equation, fa = P/A, is used for analysis. The equation A = P/Fa, is used for design. Allowable stress, Fa, includes a factor of safety.