prEN ISO 20601

• Abstract:

  This document specifies the application of phased array technology for the semi- or fully automated ultrasonic testing of fusion-welded joints in steel parts with thickness values between 3,2 mm and 8,0 mm. This meets the typical range of tube wall thickness values in boilers, which is an important application of this testing technology. The minimum and maximum value of the wall thickness range can be exceeded, when testing level "D" of this document is applied. This document applies to full penetration welded joints of simple geometry in plates, tubes, pipes, and vessels, where both the weld and parent material are low-alloy and/or fine grained steel.; NOTE "Semi-automated testing" encompasses a controlled movement of one or more probes on the surface of a component along a fixture (guidance strip, ruler, etc.), whereby the probe position is unambiguously measured with a position sensor. The probe is moved manually. "Fully automated testing" includes mechanized propulsion in addition.; Where material-dependent ultrasonic parameters are specified in this document, they are based on steels having a sound velocity of (5 920 ± 50) m/s for longitudinal waves, and (3 255 ± 30) m/s for transverse waves. It is necessary to take this fact into account when testing materials with a different velocity.; This document provides guidance on the specific capabilities and limitations of phased array technology for the detection, location, sizing and characterization of discontinuities in fusion-welded joints. Ultrasonic phased array technology can be used as a stand-alone technique or in combination with other non-destructive testing (NDT) methods or techniques, during manufacturing and testing of new welds/repair welds (pre-service testing).; This document specifies two testing levels:; — level "C" for standard situations;; — level "D" for different situations/special applications.; This document describes assessment of discontinuities for acceptance purposes based on:; — height and length;; — amplitude (equivalent reflector size) and length;; — go/no-go decision.; This document does not include acceptance levels for discontinuities.

• Status: Not Published
• Publication Date: 02-Mar-2028
• ICS: 25.160.40 - Welded joints and welds
• Technical Committee: CEN/TC 121 - Welding
• Drafting Committee: CEN/TC 121/WG 21 - Testing of welds
• Current Stage: 4020 - Submission to enquiry - Enquiry
• Start Date: 10-Sep-2026
• Completion Date: 10-Sep-2026
• Ref Project: oSIST prEN ISO 20601:2026 - Non-destructive testing of welds - Ultrasonic testing - Phased array technique for thin-walled steel components (ISO/DIS 20601:2026)

• Revises: EN ISO 20601:2018 - Non-destructive testing of welds - Ultrasonic testing - Use of automated phased array technology for thin-walled steel components (ISO 20601:2018)
• Effective Date: 20-Nov-2024

prEN ISO 20601 is a CEN draft for non-destructive testing of welds by phased array ultrasonic testing on thin-walled steel components. It specifies how to apply semi- or fully automated phased array UT to fusion-welded joints in low-alloy and/or fine-grained steel parts, mainly in the 3.2 mm to 8.0 mm wall-thickness range. It is written for people who need a repeatable method for setup, scanning, indication evaluation and reporting.

What does prEN ISO 20601 specify?

prEN ISO 20601 specifies the use of phased array technology for the ultrasonic testing of full-penetration fusion-welded joints in plates, tubes, pipes and vessels. It covers pre-service testing of new welds and repair welds, either as a stand-alone NDT method or combined with other NDT methods.

The document is organized into clauses on scope, normative references, terms, testing levels, information needed before testing, personnel and equipment, preparation, settings, blocks, procedure verification, weld testing, data storage, interpretation and reporting. Annex A is informative and gives typical reference blocks.

Annex	What it covers
A	Typical reference blocks for general use and for circumferential welds, including reflector types and typical dimensions

Clause 4 defines two testing levels, C and D. Clause 5 sets the information that must be agreed before procedure development and before testing starts. Clauses 12 to 15 cover scanning, data handling, interpretation and the test report.

What are the key requirements of prEN ISO 20601?

prEN ISO 20601 is built around a controlled, documented phased array procedure. The main practical point is that the operator must show how coverage, sensitivity, data quality and evaluation are controlled before the weld is accepted or rejected.

Testing levels and procedure control

• Testing level C is the standard approach for thin-walled components, while testing level D is for special applications such as thinner or varying thicknesses and object temperatures outside the normal range. In practice, this means the testing level must match the weld geometry and service case.
• A written test procedure is mandatory for both levels. It must define the purpose, technique, equipment, blocks, sensitivity, scan plan, evaluation method, reporting and safety aspects, so the test can be repeated in the same way.
• For level D, verification on test blocks is mandatory and the procedure itself has to be demonstrated on suitable blocks before testing starts. That gives extra proof that the setup can really find the relevant reflectors.

People and equipment

• Personnel performing the testing shall be qualified to ISO 9712 or equivalent. If indication characterization is required, the document also calls for documented training in weld shape, phased array setup, echo response and beam alignment. In practice, the tester must understand both the weld and the instrument display.
• The phased array equipment shall meet ISO 18563-1, ISO 18563-2 and ISO 18563-3 where applicable. The instrument must support suitable time-base selection, and the document recommends an A-scan sampling rate of at least six times the nominal probe frequency.
• Probes shall have a frequency of at least 5 MHz and be suitable for the component thickness. Scanning mechanisms need guides and encoders, and the probe-to-weld-centre-line distance must stay within ±1 mm unless suitability is proven another way.

Preparation, coverage and calibration

• The volume to be tested must be defined in the specification and shown on a scan plan. For manufacturing-stage tests, the document expects coverage of the weld and adjacent parent material over at least 1.25 t on each side, unless a different justified case applies.
• Scan increment along the weld shall be no more than 0.5 mm unless level D is specified. That matters because excessive increment can leave untested gaps.
• Scanning surfaces must be clean, even and free from coupling obstacles, and the surface condition has to leave no more than a 0.5 mm gap between probe shoe and surface. Surface temperature is normally limited to 0 °C to 50 °C unless special high-temperature equipment is used.
• A suitable couplant is required, and the same couplant used for sensitivity setting shall be used for the later test and checks. This keeps coupling and signal response consistent.

Blocks, checks and data handling

• Reference blocks are used for both levels C and D to set sensitivity and verify coverage. Their material, thickness and curvature must match the test object closely enough to represent the real sound path.
• Level D also requires test blocks with welds made by the same welding procedure and with similar geometry to the test object. These blocks carry real or artificial discontinuities and are used to prove coverage, sensitivity and procedure performance.
• Settings shall be checked at least every 4 h and after testing, and the complete system is checked daily before and after testing. If deviations exceed the stated limits, the settings are corrected and affected tests are repeated.
• Data acquisition shall be automatic and computer-based. All A-scan data for the tested area and all setup verification data shall be stored. During scanning, overlap is required between sections, and missed scan lines are limited so that coverage remains reliable.

Evaluation and reporting

• Interpretation starts with image quality, then identification of relevant indications, then classification, sizing and evaluation against the specified acceptance criteria. The document allows assessment by height and length, amplitude and length, or amplitude, length and characterization.
• The report must identify the object, equipment, blocks, settings, scan plan, raw data files, relevant indications and the personnel involved. In practice, the report needs to let another reviewer trace how the result was obtained.

What terms does prEN ISO 20601 define?

prEN ISO 20601 uses a small set of terms that are important for reading the procedure correctly.

• Indication / phased array indication - a pattern or disturbance in the phased array image that may need further evaluation.
• Phased array setup - the probe arrangement, including probe characteristics, probe position, number of probes and adaptation to the component curvature.
• Semi-automated testing - the probe is moved manually along a guide, while its position is measured by a sensor.
• Fully automated testing - the probe movement is mechanized in addition to position control.
• Distance-amplitude curve (DAC) - a reference curve used for sensitivity setting against reflector response at different distances.
• Time-corrected gain (TCG) - a gain method that compensates for distance so signals at different depths can be compared on the same display.
• Side-drilled hole (SDH) - a machined reflector used in reference and test blocks to set sensitivity and check coverage.
• Flat-bottomed hole (FBH) - another artificial reflector used where the test setup needs a known response source.

Who uses prEN ISO 20601?

prEN ISO 20601 is used by NDT operators, welding inspectors, procedure writers, quality managers and laboratories that test thin-walled steel welds. It is especially relevant in boiler manufacture, tube and pipe fabrication, pressure equipment work and vessel production.

It also serves contract parties that must agree testing levels, acceptance criteria, reference blocks and reporting requirements. For repair welds and new welds alike, it gives a common basis for deciding how the phased array test is set up and documented.

What changed in prEN ISO 20601 from the previous edition?

prEN ISO 20601 is the second edition and it cancels and replaces ISO 20601:2018. The foreword says this edition has been technically revised.

Which standards are used with prEN ISO 20601?

Standard	What it contributes
ISO 5577	General ultrasonic testing vocabulary
ISO 23243	Array ultrasonic testing vocabulary
ISO 9712	Qualification and certification of NDT personnel
ISO 17640	Ultrasonic testing of welds, including techniques, testing levels and assessment, and probe adaptation guidance
ISO 18563-1	Verification of phased array instruments
ISO 18563-2	Verification of array probes
ISO 18563-3	Verification of complete phased array systems
ISO 17635	General rules for metallic weld testing and links to testing levels
ISO 5817	Quality levels for fusion-welded joints in steel
ISO 23279	Characterization of discontinuities in welds
ISO/TS 16829	Selection and application of automated ultrasonic testing systems
ISO 15608	Material grouping for reference and test blocks
ISO 17636-1	Radiographic testing used to assess defects in test blocks
ISO 4761	Acceptance levels for thin-walled steel components
ISO 13588	Automated phased array ultrasonic testing for larger wall thicknesses

What does the prEN ISO 20601 document contain?

prEN ISO 20601 contains the full testing workflow, from what must be agreed before procedure development to the final report. It includes tables for testing levels and scan setup choices, requirements for blocks and reflectors, limits for scan increment and settings drift, and the information that must be recorded in the report.

It also contains figures and formulas for practical setup work, including probe shoe curvature, corrected length in circumferential welds and typical reference block arrangements. Annex A gives examples of reference blocks for calibration, DAC/TCG setup, offset checking and coverage verification, which are the parts most users will turn to during day-to-day testing.

SLOVENSKI STANDARD
01-oktober-2026
Neporušitveno preskušanje zvarnih spojev - Ultrazvočno preskušanje -
Avtomatska tehnika s faznim krmiljenjem za tankostenske sestavne dele iz jekla
(ISO/DIS 20601:2026)
Non-destructive testing of welds - Ultrasonic testing - Phased array technique for thin-
walled steel components (ISO/DIS 20601:2026)
Zerstörungsfreie Prüfung von Schweißverbindungen - Ultraschallprüfung -
Phasengesteuerte Array-Technologie für dünnwandige Bauteile aus Stahl (ISO/DIS
20601:2026)
Essais non destructifs des assemblages soudés - Contrôle par ultrasons - Technique
multiélément automatisée pour les composants en acier de parois minces (ISO/DIS
20601:2026)
Ta slovenski standard je istoveten z: prEN ISO 20601
ICS:
25.160.40 Varjeni spoji in vari Welded joints and welds
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 20601
ISO/TC 44/SC 5
Non-destructive testing of welds —
Secretariat: AFNOR
Ultrasonic testing — Phased array
Voting begins on:
technique for thin-walled steel
2026-09-07
components
Voting terminates on:
2026-11-30
Essais non destructifs des assemblages soudés — Contrôle par
ultrasons — Technique multi-éléments pour les composants en
acier à paroi mince
ICS: 25.160.40
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document has not been edited by the ISO Central Secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
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BE CONSIDERED IN THE LIGHT OF THEIR
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RECIPIENTS OF THIS DRAFT ARE INVITED
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NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 20601:2026(en)
DRAFT
ISO/DIS 20601:2026(en)
International
Standard
ISO/DIS 20601
ISO/TC 44/SC 5
Non-destructive testing of welds —
Secretariat: AFNOR
Ultrasonic testing — Phased array
Voting begins on:
technique for thin-walled steel
components
Voting terminates on:
Essais non destructifs des assemblages soudés — Contrôle par
ultrasons — Technique multi-éléments pour les composants en
acier à paroi mince
ICS: 25.160.40
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document has not been edited by the ISO Central Secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
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Published in Switzerland Reference number
ISO/DIS 20601:2026(en)
ii
ISO/DIS 20601:2026(en)
Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Testing levels . 2
5 Information required before testing . . 4
5.1 Items to be specified before procedure development .4
5.2 Specific information required by the operator before testing .4
5.3 Written test procedure .4
6 Requirements for test personnel and test equipment . 5
6.1 Qualification of test personnel .5
6.2 Test equipment .5
6.2.1 General .5
6.2.2 Instruments .5
6.2.3 Probes .5
6.2.4 Scanning mechanisms .6
7 Preparation for testing . 6
7.1 Volume to be tested .6
7.2 Verification of test setup .6
7.3 Scan increment setting .7
7.4 Geometry considerations .7
7.5 Preparation of scanning surfaces .7
7.6 Temperature .7
7.7 Couplant .7
8 Testing of parent material . 7
9 Range and sensitivity settings . 8
9.1 Settings . . .8
9.1.1 General .8
9.1.2 Pulse-echo time window .8
9.1.3 Pulse-echo sensitivity settings .8
9.2 Checking of the settings .9
9.3 Reference blocks .9
9.3.1 General .9
9.3.2 Material.9
9.3.3 Dimensions and shape .9
9.3.4 Reference reflectors .10
9.4 Test blocks for testing level D . .10
9.4.1 General .10
9.4.2 Material.10
9.4.3 Dimensions and shape .10
9.4.4 Reflectors in test blocks .11
10 Checks of test equipment .11
11 Verification of the test procedure .11
12 Weld testing.11
13 Data storage .12
14 Interpretation and analysis of phased array data .12
14.1 General . 12
14.2 Assessing the quality of the phased array data . 12
14.3 Identification of relevant indications . 13

iii
ISO/DIS 20601:2026(en)
14.4 Classification of relevant indications . 13
14.5 Determination of location and length . 13
14.5.1 Location . 13
14.5.2 Length . 13
14.6 Indication assessment . 13
14.6.1 General . 13
14.6.2 Assessment based on height and length.14
14.6.3 Assessment based on amplitude and length .14
14.6.4 Characterization of discontinuities .14
14.7 Evaluation against acceptance criteria .14
15 Test report . 14
Annex A (informative) Typical reference blocks .16
Bibliography .18

iv
ISO/DIS 20601:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee
SC 5, Testing and inspection of welds.
This second edition cancels and replaces the first edition (ISO 20601:2018) which has been technically
revised.
Any feedback, question or request for official interpretation related to any aspect of this document should be
directed to the Secretariat of ISO/TC 44/SC 5 via your national standards body. A complete listing of these
bodies can be found at www.iso.org/members.html. Official interpretations, where they exist, are available
from this page: https://committee.iso.org/sites/tc44/home/interpretation.html.

v
DRAFT International Standard ISO/DIS 20601:2026(en)
Non-destructive testing of welds — Ultrasonic testing —
Phased array technique for thin-walled steel components
1 Scope
This document specifies the application of phased array technology for the semi- or fully automated
ultrasonic testing of fusion-welded joints in steel parts with thickness values between and including 3,2 mm
and 8,0 mm. This meets the typical range of tube wall thickness values in boilers, which is an important
application of this testing technology. The minimum and maximum value of the wall thickness range can
be exceeded, when testing level “D” of this document is applied. This document applies to full penetration
welded joints of simple geometry in plates, tubes, pipes, and vessels, where both the weld and parent
material are low-alloy and/or fine grained steel.
NOTE “Semi-automated testing” encompasses a controlled movement of one or more probes on the surface of a
component along a fixture (guidance strip, ruler, etc.), whereby the probe position is unambiguously measured with a
position sensor. The probe is moved manually. “Fully automated testing” includes mechanized propulsion in addition.
Where material-dependent ultrasonic parameters are specified in this document, they are based on steels
having a sound velocity of (5 920 ± 50) m/s for longitudinal waves, and (3 255 ± 30) m/s for transverse
waves. It is necessary to take this fact into account when testing materials with a different velocity.
This document provides guidance on the specific capabilities and limitations of phased array technology
for the detection, location, sizing and characterization of discontinuities in fusion-welded joints. Ultrasonic
phased array technology can be used as a stand-alone technique or in combination with other non-
destructive testing (NDT) methods or techniques, during manufacturing and testing of new welds/repair
welds (pre-service testing).
This document specifies two testing levels:
— level “C” for standard situations;
— level “D” for different situations/special applications.
This document describes assessment of discontinuities for acceptance purposes based on:
— height and length;
— amplitude (equivalent reflector size) and length;
— go/no-go decision.
This document does not include acceptance levels for discontinuities.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 5577, Non-destructive testing — Ultrasonic testing — Vocabulary
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and assessment

ISO/DIS 20601:2026(en)
ISO 18563-1, Non-destructive testing — Characterization and verification of ultrasonic phased array equipment
— Part 1: Instruments
ISO 18563-2, Non-destructive testing — Characterization and verification of ultrasonic phased array equipment
— Part 2: Array probes
ISO 18563-3, Non-destructive testing — Characterization and verification of ultrasonic phased array equipment
— Part 3: Complete systems
ISO 23243, Non-destructive testing — Ultrasonic testing with arrays — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 5577 and ISO 23243and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
indication, noun
phased array indication, noun
pattern or disturbance in the phased array image which may need further evaluation
3.2
phased array setup, noun
probe arrangement defined by probe characteristics (e.g. frequency, probe element size, beam angle, wave
mode), probe position, and the number of probes, adaptation to the curvature of the test object
[SOURCE: ISO 23243 , text added "adaptation to the curvature of the test object"]
4 Testing levels
Quality requirements for welded joints are mainly associated with the material, welding process and service
conditions. To comply with these requirements, this document specifies two testing levels “C” and “D”.
a) A written procedure is mandatory for both testing levels C and D.
b) Testing level C applies to the standardized approach for thin-walled components (see Table 1 and
Table 2), e.g. testing from two sides or testing from one side of the weld when the cap is removed.
c) Testing level D shall be agreed upon for special applications, e.g. tests on wall thickness below 3,2 mm,
varying thicknesses (counter bore) and tests at object temperatures outside the range specified in 7.6.
[1]
NOTE For larger wall thicknesses, ISO 13588 applies.
d) For testing level D, verification on test blocks is mandatory.
[2]
In general, the testing levels are related to quality levels (given in ISO 5817 , for example). The appropriate
[3]
testing level can be specified by standards for weld testing (e.g. ISO 17635 ), product standards or other
specifications.
[3]
e) When ISO 17635 is specified, the recommended testing levels are as given in Table 1.

ISO/DIS 20601:2026(en)
Table 1 — Recommended testing levels
[2]
Testing level Quality level in ISO 5817
C B, C, D
D Special applications
Table 2 shows the minimum requirements for the phased array modes for testing levels C and D.
f) The setup shall be verified with reference and/or test blocks; as described in 7.2.
g) In cases where scanning is performed from one scanning surface (e.g. the outer surface of a vessel), at
least half and full skip shall be used.
h) If scanning is performed from both scanning surfaces (e.g. top and bottom surfaces), testing at half skip
could be sufficient, depending on weld and probe dimensions.
i) If the evaluation of the indications is based on amplitude only, the deviation of the beam axis from the
normal to the weld bevel shall not exceed 6°.
j) In case it is not possible to stay within this 6° value, because of the geometry of the test object (e.g. weld
cap, narrow gap weld), the scan plan shall describe the corrective measures and explain how the areas
outside the 6° requirement are covered with sufficient sensitivity.
Table 2 — Description of test setup depending on testing levels
Test setup Testing levels
Examples
Phased array
Scanning C D
mode
line scanning (at
electronic linear
fixed distance to Two sides To be specified
scanning
weld)
electronic secto-
line scanning (at Two sides or two
rial scanning or
fixed distance to probe positions To be specified
combined elec-
weld) on the same side
tronic scanning
electronic sectori- area scanning One side, weld cap
To be specified
al scanning (raster, meander) removed
line scanning (at
a
Skewed scan fixed distance to Not applicable To be specified
weld)
a
If detection of transverse discontinuities is required by specification, a suitable additional test setup shall be applied. Skewed
probe or electronically skewed beam can be used.

ISO/DIS 20601:2026(en)
5 Information required before testing
5.1 Items to be specified before procedure development
Information on the following items is required:
a) purpose and extent of testing;
b) type(s) of parent material (i.e. cast, forged, rolled), grain size;
c) testing levels;
d) acceptance criteria;
e) specification of reference blocks;
f) manufacturing or operational stage at which the testing has to be carried out;
g) weld details and information on the size of the heat-affected zone;
h) requirements for access, surface conditions and temperature;
i) personnel qualifications;
j) reporting requirements.
5.2 Specific information required by the operator before testing
Before any testing of a welded joint can begin, the operator shall have access to all the information specified
in 5.1, together with the following additional information:
a) written test procedure;
b) joint preparation and dimensions;
c) relevant information on the welding process;
d) time of inspection relative to any post-weld heat treatment.
5.3 Written test procedure
For all testing levels, a written test procedure is required.
The procedure shall include the following information as a minimum:
a) purpose and extent of testing;
b) testing techniques;
c) testing levels;
d) personnel qualification, training requirements;
e) test equipment to be used (including frequency, sampling rate, pitch between elements, element size);
f) reference and/or test blocks;
g) sensitivity and range setting of test equipment;
h) available access and surface conditions;
i) testing of parent material;
j) example of reference scan;
ISO/DIS 20601:2026(en)
k) evaluation of indications;
l) acceptance levels and/or recording levels;
m) scan plan showing probe placement, movement, and c
...