Define the term "false indication" in ultrasonic testing.

In ultrasonic testing, a "false indication" refers to an echo signal that suggests a flaw is present when there is none. This situation can arise due to various factors such as signal noise, equipment malfunction, or improper technique. Identifying a false indication is crucial because it can lead to unnecessary repairs or further testing, which may have financial and operational implications.

Understanding that a false indication does not correspond to any actual defect is vital for the integrity of testing results. It underscores the importance of the technician’s skill in interpreting signals accurately and the necessity of proper calibration and technique in ultrasonic testing. By distinguishing between actual flaws and false indications, operators can effectively ensure the reliability of the structures being tested and maintain safety standards.