No single inspection technique is adequate for all types of materials and a single-technology system is only used for a narrow range of applications. The eddy current (EC) technique is commonly used to inspect nonferromagnetic materials. Remote field testing (RFT) and magnetic flux leakage (MFL) techniques are used for the inspection of ferritic materials and carbon steel tubes. The internal rotary inspection system (IRIS) ultrasound technique is used for tube profilometry and corrosion mapping,
and is a reliable validation technique for eddy current, remote field, and magnetic flux leakage inspections of any material.