An innovative apparatus and method have been developed that can volumetrically examine any dielectric material, including polyethylene piping and non-metallic pipe repairs. The method employs a first of a kind apparatus that is based on the application of microwave energy. Comprehensive laboratory
testing of the method and apparatus has been completed including the inspection of many samples of polyethylene pipe welds and non-metallic pipe repairs. The specimens examined had different types of internal flaws that commonly occur in industrial application. The apparatus has been shown capable of detecting the presence of internal flaws, such as lack of fusion and inclusions in polyethylene pipe welds, thickness changes and voids in polyethylene pipe, delaminations and lack of adhesion at the substrate of a non-metallic pipe repair.  Additionally, the method has been tested in field applications.  This paper will describe the method and apparatus and provide  examples of polyethylene pipe weld and non-metallic pipe  repair examinations.