Preparatory Notes for ASNT NDT Level III Examination - Ultrasonic Testing, UT

IIW type blocks are used to calibrate instruments for both angle beam and
normal incident inspections. Some of their uses include setting metal-distance
and sensitivity settings, determining the sound exit point and refracted angle
of angle beam transducers, and evaluating depth resolution of normal beam
inspection setups. Instructions on using the IIW type blocks can be found in
the annex of American Society for Testing and Materials Standard E164,
Standard Practice for Ultrasonic Contact Examination of Weldments.
The Miniature Angle-Beam or ROMPAS Calibration Block