What happens when a weld fails in a critical structure like a bridge or ship? Delays, safety risks, and costly repairs. But what if that failure was avoidable? In this episode of the Industrial Welding Inspection Podcast, host John Masseny uncovers the hidden threat behind many weld defects—slag inclusions. These non-metallic materials can lurk within welds, weakening them and leading to unexpected failures. Join us as we explore how slag inclusions form during processes like shielded metal arc welding (SMAW) and flux-cored arc welding (FCAW), why they're so dangerous, and the advanced inspection methods used to detect them. From visual checks to ultrasonic and radiographic testing, we break down the pros and cons of popular non-destructive testing (NDT) techniques. You'll also hear a real-world story from a welding inspector who stopped a disaster in its tracks with a timely ultrasonic test. Learn the best practices for preventing inclusions through proper training, clean work environments, and correct weld procedures. This episode delivers practical knowledge for inspectors, welders, and project managers determined to ensure safety and quality in every weld. Tune in, subscribe, and share as we continue to decode the secrets behind welding inspection and integrity. Have a question or topic suggestion? Reach out—we’d love to hear from you. Stay safe and keep inspecting!