UT study: read the reference-block information before setup
A position label needs a reference point as well as a value. Two notes can give different numbers for the same location when they start from opposite ends. These short reading exercises help you identify what a reference-block description supplies and explain a location 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.
Can two position notes identify the same mark?
Draw a line on paper and divide it into 30 equal spaces. Label its left end L and its right end R. Put a mark eight spaces from L. All counts below run along that line, starting at the stated end. This original paper exercise uses counted spaces so you can focus on the reference point.
Before reading the answer, decide which of the four notes identifies the mark you drew. Sketch the position described by each complete note.
| Note | Position stated | Your question |
|---|---|---|
| A | 8 spaces from L | Where does the count start? |
| B | 22 spaces from R | Does this reach the same mark as A? |
| C | 8 spaces from R | Where would this place the mark? |
| D | 8 spaces | Which end was used? |
Keep the reference point with the number
Notes A and B identify the same mark. Eight spaces from L leave 22 spaces to R, because 30 − 8 = 22. You can check the pair by adding the two distances, 8 + 22 = 30.
Note C starts at R and counts eight spaces toward L. It lands 22 spaces from L, on the other side of the line. Repeating the number eight while changing the starting end changes the location.
Note D leaves the starting end open. Ask “Eight spaces from L or from R?” before placing it. A complete note for your original mark is “8 spaces from L, equivalent to 22 spaces from R.”
Carry that habit back to the lesson handout. Keep the named surface or reference point beside each location value and its unit. Use the full drawing and the assigned instructions when interpreting an actual block.
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 November 6, 2026. Follow the current requirements from your employer or certification body when planning qualification or an examination.