UT study: read the reference-block information before setup
Before using a reference block in an ultrasonic testing lesson, explain the information supplied with it. A number means little until you know its units and what it describes. This reading exercise helps you turn a block description into clear study notes before following the lesson’s setup instructions.
Name the learning task before reading the block
Start with a sentence: “In this exercise, I am being asked to identify _____.” Complete it from the lesson prompt. That keeps a question about a drawing label from becoming an unsupported conclusion about instrument readiness.
Evident distinguishes reference calibration for a particular test from calibration certification of an instrument. Its tutorial places the details of reference calibration in the procedure for the specific test. Reading a block description does not replace those instructions.
Sources: Evident: calibration concepts.
Read three parts of the block description
Evident’s block catalog lists different materials, unit systems and reference features. Read the complete description supplied for your exercise. A familiar outline or short block name is not the whole description.
| Information | What to write in your notes | Question to resolve if unclear |
|---|---|---|
| Material | The material stated in the exercise. | Where is the material identified? |
| Units | The unit attached to the dimension or specified by the drawing. | Which unit applies to this label? |
| Feature and dimension | The named feature and the dimension the label describes. | Does this label describe size, location or something else? |
Sources: Evident: test-block descriptions.
Practice with a text-only drawing key
Imagine a fictional lesson handout with this key: “A identifies the block’s overall thickness. B identifies the diameter of the labeled hole. C identifies the distance from the named surface to the hole’s center.” The handout supplies no numerical values. This is an original comprehension exercise, not a block specification or official examination question.
Before looking at the answer, decide which label answers each question below. Use only the relationships stated in the key.
- Which label tells you how thick the block is overall?
- Which label identifies the size of the hole?
- Which label identifies the hole center’s location relative to a named surface?
Explain each answer and what is still missing
The answers are A, B and C, respectively. The key assigns a different meaning to each label. B and C both refer to the same hole, but one concerns its diameter and the other concerns its location. Substituting one for the other changes the question being answered.
You can explain those relationships without calculating a dimension. You cannot supply the missing values or units from this handout. Write “value not supplied” or “unit not supplied” where appropriate; leave the question open until the lesson provides the information.
Now imagine a cropped copy shows only “B” beside an unlabeled number, without the key or a unit note. A useful study question is: “What does B identify, and which unit belongs to this value?” Guessing from the page layout would hide exactly what needs clarification.
Carry the reading skill into your UT course
NDTAcademy’s ultrasonic testing curriculum includes Instrument Standardization and Reference Blocks, Inspection Standardization with Reference Blocks, and a Level I Instrument and Reference-Block Standardization Lab. Use the information-reading exercise to prepare for those lessons, then follow their assigned instructions.
This article provides no calibration sequence, instrument settings or acceptance limits. It also does not establish that two blocks are interchangeable. Formal training and personnel certification remain separate: course completion alone does not grant authorization to perform an examination.
If you are still choosing a course, start with the public UT sample and the training-versus-certification guide. For a team, compare the planned training with the employer’s applicable qualification requirements before allocating seats.
Sources and further reading
Sources checked on September 29, 2026. Follow the current requirements from your employer or certification body when planning qualification or an examination.