In this paper, we carried out PIND (Particle Impact Noise Detection) test and X-ray inspection of a transistor in a TO-18 package for commercial and industrial applications. From our evaluation results, we explain the validity of the PIND test by comparing PIND test and X-ray inspection results. We make clear that PIND test is able to detect internal foreign material that may be transparent to X-ray inspection. In addition, we report analysis results of internal foreign materials from defective devices. This matter suggests that a problem is contamination control in the manufacturing process, most likely the sealing process.