The article presents issues concerning the formation of root geometry indications in conventional ultrasonic tests and in the Phased Array tests. In addition, the article describes the manner enabling the verification of sources of indications allowing their proper classification both in classical and Phased Array tests. The article contains results of T-joint-related tests performed using the Phased Array technique and depicting the scale of geometry indications when testing welded joints. The article is addressed to NDT personnel performing ultrasonic tests.