SIST EN ISO 12716:2026

• Abstract:

  This document defines the terms used in acoustic emission testing and forms a common basis for standards and general use.

• Status: Published
• Public Enquiry End Date: 30-Jul-2025
• Publication Date: 29-Sep-2026
• ICS: 01.040.19 - Testing (Vocabularies)
• ICS: 19.100 - Non-destructive testing
• Technical Committee: PKG - Testing of metallic materials
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 27-May-2026
• Due Date: 01-Aug-2026
• Completion Date: 30-Sep-2026
• Ref Project: EN ISO 12716:2026 - Non-destructive testing - Acoustic emission testing - Vocabulary (ISO 12716:2026)

• Referred By: SIST EN 12817:2010 - LPG Equipment and accessories - Inspection and requalification of LPG tanks up to and including 13 m3
• Effective Date: 27-May-2026
• Referred By: SIST-TP CEN ISO/TR 25108:2007 - Non-destructive testing - Guidelines for NDT personnel training organizations (ISO/TR 25108:2006)
• Effective Date: 27-May-2026
• Referred By: SIST EN ISO 18081:2024 - Non-destructive testing - Acoustic emission testing (AT) - Leak detection by means of acoustic emission (ISO 18081:2024)
• Effective Date: 27-May-2026
• Referred By: SIST-TP CEN ISO/TR 25107:2007 - Non-destructive testing - Guidelines for NDT training syllabuses (ISO/TR 25107:2006)
• Effective Date: 27-May-2026
• Referred By: SIST-TS CEN/TS 13445-501:2019 - Unfired pressure vessels - Acoustic emission for pressure vessels
• Effective Date: 27-May-2026
• Referred By: SIST EN 12819:2010 - LPG equipment and accessories - Inspection and requalification of LPG tanks greater than 13 m3
• Effective Date: 27-May-2026
• Referred By: SIST EN ISO 18081:2017 - Non-destructive testing - Acoustic emission testing (AT) - Leak detection by means of acoustic emission (ISO 18081:2016)
• Effective Date: 27-May-2026
• Referred By: SIST EN ISO 16148:2006 - Gas cylinders - Refillable seamless steel gas cylinders - Acoustic emission testing (AT) for periodic inspection (ISO 16148:2006)
• Effective Date: 27-May-2026
• Referred By: SIST EN 12817:2019 - LPG Equipment and accessories - Inspection and requalification of LPG pressure vessels up to and including 13 m³
• Effective Date: 27-May-2026
• Referred By: SIST EN 12819:2019 - LPG equipment and accessories - Inspection and requalification of LPG pressure vessels greater than 13 m³
• Effective Date: 27-May-2026
• Referred By: SIST EN 13477-1:2001 - Non-destructive testing - Acoustic emission - Equipment characterisation - Part 1: Equipment description
• Effective Date: 27-May-2026
• Revises: SIST EN 1330-9:2017 - Non-destructive testing - Terminology - Part 9: Terms used in acoustic emission testing
• Effective Date: 20-Dec-2023

Overview

SIST EN ISO 12716:2026 is an international standard that establishes a comprehensive vocabulary for acoustic emission testing as part of non-destructive testing (NDT). Developed by the Slovenian Institute for Standardization (SIST), in alignment with ISO/TC 135/SC 9, this standard ensures consistent communication by defining key terminology related to acoustic emission methods. The vocabulary specified serves as a foundational reference for further standards, technical documents, and daily use in the NDT field, fostering clarity and efficiency across industries, regulatory contexts, and technical communities.

Key Topics

SIST EN ISO 12716:2026 covers a wide range of terms relevant to acoustic emission testing. The structured vocabulary is organized according to scientific and technical relationships, and includes:

• Physical Principles: Terms describing the fundamental nature of acoustic emission (AE), AE events, sources, waves, event mechanisms, and energy release (including phenomena like the Kaiser and Felicity effects).
• Detection and Signal Acquisition: Definitions explaining signals, burst and continuous signals, detection thresholds, signal features (arrival time, duration, amplitude, energy), and decibel calibration for AE measurements.
• Equipment and Accessories: Descriptions of devices such as AE sensors, integrated sensors, waveguides, couplants, signal generators, Hsu-Nielsen sources, channels, and the concept of dynamic range in instrumentation.
• Data Analysis: Concepts around interpreting and evaluating AE signals, hit counting, statistical distributions, activity levels, intensity assessments, correlation plots, and time series plotting.
• Application Procedures: Terminology related to the practical steps in testing, including stimulation methods, noise differentiation, testing areas, attenuation, detectability, sensor arrays and event location techniques (zone, linear, planar, and 3-D localization, along with AI-driven methods).

Applications

Acoustic emission testing as defined in SIST EN ISO 12716:2026 is widely used in the following practical contexts:

• Structural Health Monitoring: AE testing is crucial for monitoring the integrity of structures such as bridges, pipelines, storage tanks, and pressure vessels - detecting cracks, corrosion, and other defects without causing damage.
• Manufacturing and Process Control: The terminology supports quality assurance during production, allowing early detection of material flaws, leaks, or abnormal operational events.
• Maintenance and Lifespan Extension: Non-destructive evaluation with AE techniques enables predictive maintenance, reducing downtime and extending the operational life of costly infrastructure.
• In-service Surveillance: The standard aids in continuously monitoring equipment during normal operations, providing real-time alerts for material degradation or mechanical failure.
• Research and Development: A shared vocabulary ensures effective collaboration and knowledge transfer across laboratories, universities, and industrial R&D centers involved in advancing AE technology and methodologies.

By standardizing these terms, organizations can minimize misunderstandings, optimize testing procedures, and facilitate international cooperation and trade.

Related Standards

SIST EN ISO 12716:2026 aligns closely with other key standards in non-destructive testing and acoustic emission technology, including:

• EN 1330-9:2017: Non-destructive testing – Terminology Part 9: Terms used in acoustic emission testing
• ASTM E1316: Standard Terminology for Nondestructive Examinations, Section B: Acoustic Emission
• ISO Online Browsing Platform and IEC Electropedia: Authoritative sources for harmonized international NDT terminology

These related standards further support the consistent application and integration of acoustic emission testing terminology in global industry and technical documentation.

Keywords: acoustic emission testing, non-destructive testing, SIST EN ISO 12716, AE signals, sensor, terminology, standardization, NDT vocabulary, AE event location, industry standards, structural health monitoring, AE equipment, ISO 12716

SLOVENSKI STANDARD
01-november-2026
Neporušitvene preiskave - Akustična emisija - Terminologija (ISO 12716:2026)
Non-destructive testing - Acoustic emission testing - Vocabulary (ISO 12716:2026)
Zerstörungsfreie Prüfung - Schallemissionsprüfung - Terminologie (ISO 12716:2026)
Essais non destructifs - Contrôle par émission acoustique - Vocabulaire (ISO
12716:2026)
Ta slovenski standard je istoveten z: EN ISO 12716:2026
ICS:
01.040.19 Preskušanje (Slovarji) Testing (Vocabularies)
19.100 Neporušitveno preskušanje Non-destructive testing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 12716
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2026
EUROPÄISCHE NORM
ICS 01.040.19; 19.100 Supersedes EN 1330-9:2017
English Version
Non-destructive testing - Acoustic emission testing -
Vocabulary (ISO 12716:2026)
Essais non destructifs - Contrôle par émission Zerstörungsfreie Prüfung - Schallemissionsprüfung -
acoustique - Vocabulaire (ISO 12716:2026) Terminologie (ISO 12716:2026)
This European Standard was approved by CEN on 10 May 2026.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12716:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 12716:2026) has been prepared by Technical Committee ISO/TC 135 "Non-
destructive testing" in collaboration with Technical Committee CEN/TC 138 “Non-destructive testing”
the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2026, and conflicting national standards
shall be withdrawn at the latest by November 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 1330-9:2017.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 12716:2026 has been approved by CEN as EN ISO 12716:2026 without any modification.

International
Standard
ISO 12716
Second edition
Non-destructive testing — Acoustic
2026-05
emission testing — Vocabulary
Essais non destructifs — Contrôle par émission acoustique —
Vocabulaire
Reference number
ISO 12716:2026(en) © ISO 2026
ISO 12716:2026(en)
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
ISO 12716:2026(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms related to the physical nature of acoustic emission .1
3.2 Terms related to the detection and acquisition of acoustic emission signals .2
3.3 Terms related to the equipment and accessories used for acoustic emission testing .6
3.4 Terms related to the analysis of acoustic emission signals .8
3.5 Terms relating to the application of acoustic emission testing .10
Bibliography . 14
Index .15

iii
ISO 12716:2026(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 document 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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 135, Non-destructive testing, Subcommittee
SC9, Acoustic emission testing., in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 138, Non-destructive testing, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 12716:2001), which has been technically
revised.
The main changes are as follows:
— terms sorted in order of scientific and technical characteristics;
— terms and definitions revised and obsolete terms removed.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
International Standard ISO 12716:2026(en)
Non-destructive testing — Acoustic emission testing —
Vocabulary
1 Scope
This document defines the terms used in acoustic emission testing and forms a common basis for standards
and general use.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 Terms related to the physical nature of acoustic emission
3.1.1
acoustic emission
AE
class of phenomena whereby transient elastic waves are generated by the rapid release of energy from
localized sources or the transient waves so generated
Note 1 to entry: Local plastic deformation, crack propagation, erosion, corrosion, impact, leakage are examples of such
phenomena.
3.1.2
acoustic emission event
event
physical phenomenon giving rise to acoustic emission (3.1.1)
3.1.3
acoustic emission source
source
spatial element from where one (or more) acoustic emission event(s) (3.1.2) originate(s)
3.1.4
acoustic emission wave
elastic wave
transient elastic wave generated by an acoustic emission event (3.1.2)
Note 1 to entry: Acoustic emission and acoustic emission wave are often used synonymously.

ISO 12716:2026(en)
3.1.5
acoustic emission event mechanism
event mechanism
process or combination of processes, generating characteristic acoustic emission events (3.1.2)
Note 1 to entry: AE event mechanisms can be subdivided into several categories: material and mechanical, macroscopic
and microscopic, primary and secondary.
Note 2 to entry: Instead of event mechanism, the term source mechanism is frequently used in AE literature. Source
mechanism relates to the origin of the AE waves radiated in the course of characteristic AE events. In this sense, event
mechanism and source mechanism are synonymic.
3.1.6
acoustic emission event energy
event energy
elastic energy released by an acoustic emission event (3.1.2)
Note 1 to entry: The event energy in units of joule (watt-second) is the integral of the event energy release rate
(equivalent to the event power) over the duration of the event process.
3.1.7
Kaiser effect
absence of significant acoustic emission until the previous maximum applied load level has been exceeded
Note 1 to entry: The definition of the significant acoustic emission depends on the application.
3.1.8
Felicity effect
appearance of significant acoustic emission at a load level below the previous maximum applied level, e.g. as
observed in composite materials
Note 1 to entry: The definition of the significant acoustic emission depends on the application.
3.1.9
Felicity ratio
ratio between the applied load at which significant acoustic emission reappears during the next application
of loading and the previous maximum applied load
Note 1 to entry: The definition of the significant acoustic emission depends on the application.
3.2 Terms related to the detection and acquisition of acoustic emission signals
3.2.1
acoustic emission signal
electrical signal from an acoustic emission sensor (3.3.1) converted from the acoustic emission wave (3.1.4)
Note 1 to entry: This includes burst signals as well as continuous signals.
3.2.2
burst signal
acoustic emission signal (3.2.1) having an identifiable beginning and an identifiable end
Note 1 to entry: See Figure 1.

ISO 12716:2026(en)
Key
X time in units of µs
Y signal voltage in units of mV
1 burst signal beginning
2 burst signal end
3 acoustic emission detection threshold
Figure 1 — Burst signal
3.2.3
acoustic emission detection threshold
detection threshold
threshold
voltage level, usually stated in units of dB , that needs to be exceeded in order to detect a burst signal (3.2.2)
AE
3.2.4
burst signal beginning
recognized start of a burst signal (3.2.2), defined as the first time that the signal crosses the detection
threshold (3.2.3)
3.2.5
burst signal end
recognized termination of a burst signal (3.2.2), defined as the last time that the signal crosses the detection
threshold (3.2.3) for a preset period of time
3.2.6
burst signal features
characteristic quantities describing a burst signal (e.g. arrival time, peak amplitude, duration, rise time,
energy)
Note 1 to entry: See Figure 2. Energy is not marked here.

ISO 12716:2026(en)
Key
1 burst signal rise time
2 burst signal peak amplitude
3 acoustic emission detection threshold
4 time
5 burst signal duration
6 burst signal ring down count
7 signal voltage
8 first threshold crossing, arrival time
9 last threshold crossing
Figure 2 — Basic features of a burst signal
3.2.7
burst signal arrival time
arrival time
time when a burst signal first exceeds the detection threshold (3.2.3)
3.2.8
burst signal rise time
rise time
time interval between the burst signal beginning (3.2.4) and the time of the peak amplitude
3.2.9
burst signal peak amplitude
amplitude
maximum rectified signal voltage within the burst signal duration
3.2.10
acoustic emission decibel
relative unit of measurement for the electric output signal of an acoustic emission sensor (3.3.1)
Note 1 to entry: The following formula is applied for conversion to the acoustic emission decibel scale:
AU20log /U

10 sr
where
A is the output signal voltage in units of acoustic emission decibel (dB );
AE
U is the rectified output signal voltage in units of µV;
s
U is the reference output signal voltage equal to 1 µV.
r
ISO 12716:2026(en)
3.2.11
burst signal duration
duration
time interval between the burst signal beginning (3.2.4) and the burst signal end (3.2.5)
3.2.12
burst signal ring down count
count
N
number of times a burst signal exceeds the detection threshold (3.2.3) in one signal polarity within the burst
signal duration (3.2.11)
3.2.13
burst signal energy
energy
integral of the squared signal voltage within the duration of the burst signal (3.2.2)
3.2.14
burst signal strength
signal strength
integral of the rectified signal voltage within the duration of the burst signal (3.2.2)
3.2.15
continuous signal
acoustic emission signal (3.2.1) having no identifiable beginning and end
Note 1 to entry: Continuous signals can be observed when numerous similar burst signals overlap. Examples are
turbulent flow of a fluid in a leak path or global plastic deformation of a metal.
Note 2 to entry: See Figure 3.
Key
X time in units of µs
Y signal voltage in units of mV
Figure 3 — Continuous signal
ISO 12716:2026(en)
3.2.16
continuous signal features
characteristic quantities describing a continuous signal (3.2.15), e.g. average signal level (ASL) and root mean
square (RMS) signal voltage
3.3 Terms related to the equipment and accessories used for acoustic emission testing
3.3.1
acoustic emission sensor
sensor
device using a sensing element to convert the surface movement produced by an acoustic emission wave
(3.1.4) into an electrical output signal excluding amplification
3.3.2
integrated acoustic emission sensor
integrated sensor
device for integrating the preamplifier or other signal acquisition devices with
...