1.1 ,This practice covers the procedure for sorting ferrous metals using the electromagnetic (eddy current/magnetic induction) method. The procedure relates to instruments using absolute or comparator-type coils for distinguishing variations in mass, shape, conductivity, permeability, and other variables such as hardness and alloy that affect the electromagnetic or magnetic properties of the material. The selection of reference standards to determine sorting feasibility and to establish standards is also included.2