A golf club head having a composite face insert attached to a metallic body is provided. It is then ascertained whether each failed component should be repaired or replaced, and whether any component related to a failed component should be maintained. Thus, the helmet is forcibly ventilated while the user wearing the helmet participates in rapid leisure sports, so that the helmet does not generate any odor caused by the heat and sweat in the interior of the helmet and maintains a pleasant and comfortable atmosphere. Some embodiments of the present invention also enable the use of positive mode conditions with PFET test structures, which provides for improved contrast in the VC images, improving the effectiveness of the defect detection achieved with VC imaging.