oSIST prEN 13477-1:2026

SLOVENSKI STANDARD
01-februar-2026
Neporušitvene preiskave - Preskušanje z akustično emisijo - Karakterizacija
opreme - 1. del: Opis opreme
Non-destructive testing - Acoustic emission testing - Equipment characterization - Part 1:
Equipment description
Zerstörungsfreie Prüfung - Schallemissionsprüfung - Gerätecharakterisierung - Teil 1:
Gerätebeschreibung
Essais non destructifs - Essais d'émission acoustique - Caractérisation de l'équipement -
Partie 1: Description de l'équipement
Ta slovenski standard je istoveten z: prEN 13477-1
ICS:
19.100 Neporušitveno preskušanje Non-destructive testing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2026
ICS 19.100 Will supersede EN 13477-1:2001
English Version
Non-destructive testing - Acoustic emission testing -
Equipment characterization - Part 1: Equipment
description
Essais non destructifs - Essais d'émission acoustique - Zerstörungsfreie Prüfung - Schallemissionsprüfung -
Caractérisation de l'équipement - Partie 1: Description Gerätecharakterisierung - Teil 1: Gerätebeschreibung
de l'équipement
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 138.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

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. prEN 13477-1:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Overview . 5
5 Piezoelectric Sensor . 8
5.1 General. 8
5.2 Sensing element . 8
5.3 Sensor characteristics . 8
5.4 Sensor housing . 9
6 Signal conditioning . 10
6.1 General. 10
6.2 Preamplifier . 10
6.3 Cables . 10
6.4 Post-amplification and frequency filtering . 11
7 Signal acquisition . 11
7.1 Analogue-to-digital conversion . 11
7.2 Burst signal . 13
7.3 Continuous signal . 14
7.4 Waveform . 14
8 Data representation . 14
9 Data processing . 15
10 Automated systems . 15
10.1 General. 15
10.2 Automated data acquisition . 15
10.3 Automated data processing. 15
10.4 Automated reporting . 16
10.5 Automated supervision . 16
Bibliography . 17

European foreword
This document (prEN 13477-1:2026) has been prepared by Technical Committee CEN/TC 138
“Non-destructive testing”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 13477-1:2001.
EN 13477-1:2001:
— Clause 4 “Overview” added.
EN 13477, Non-destructive testing — Acoustic emission testing — Equipment characterization, consists
of the following parts:
— Part 1: Equipment description;
— Part 2: Verification of operating characteristics.
Part 1 of this document describes the main components of an acoustic emission testing system.
Part 2 of this document gives methods and acceptance criteria for verifying routinely the electronic
performance of an acoustic emission testing system composed of one or more acoustic emission
channels during its lifetime.
Introduction
Most of the acoustic emission testing systems for industrial applications are based on the utilization of
piezoelectric sensors. This sensor technology usually offers high sensitivity as well as reliability and is
sufficiently robust at the same time. Piezoelectric sensors have been used successfully for decades in
the field of acoustic emission testing and thus a wide range of different piezoelectric sensor types and
models produced by various equipment manufacturers are available.
Therefore, this document describes the equipment used for utilizing piezoelectric sensors as this
technology is the most widespread one.
1 Scope
This document describes the main components that constitute an acoustic emission testing system on
the basis of the utilization of piezoelectric sensors. Each component is assigned to one of the following
list items:
a) piezoelectric sensor;
b) signal conditioning;
c) signal acquisition;
d) analysis and output of results.
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.
EN 1330-1:2014, Non-destructive testing — Terminology — Part 1: List of general terms
EN 1330-2:1998, Non-destructive testing — Terminology — Part 2: Terms common to the non-destructive
testing methods
EN 1330-9:2017, Non-destructive testing — Terminology — Part 9: Terms used in acoustic emission
testing
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 1330-1:2014, EN 1330-2:1998
and EN 1330-9:2017 apply.
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/
4 Overview
The measurement chain employed in acoustic emission testing (AT) is based predominately on
piezoelectric sensors and can be divided into three sections: the piezoelectric sensor is designated as
section 1, the signal conditioning as section 2 and the signal acquisition as section 3.
The piezoelectric sensor is usually mounted directly onto the surface of the test object and constitutes
section 1 of each measurement chain for the detection of acoustic emission (AE) released in the course
of the test. Generally, the output signal of the sensor shall represent the characteristic response to the
surface displacement caused by the elastic wave arriving at the sensor's sensitive face. In case of burst
emission, the output signal of the sensor can be separated in time into single AE signals. In case of
continuous emission, a high number of burst emissions superpose so that no clear separation into
single burst emissions is possible anymore. However, the output signal due to continuous emission shall
be characteristic of the excitation at the sensor’s sensitive face as well.
The excitation at the sensitive face of such an AE sensor may be described by the normal component of
the surface displacement u at the sensor position x as a function of time t. Figure 1 a) shows an
XD
example in terms of the output signal voltage s in time t of a broadband capacitive sensor
C
(displacement sensor) in response to a single burst emission due to the breakage of a glass capillary at
the surface of a steel test block. The glass capillary is positioned in close vicinity to the capacitive sensor
and at the midway point to a resonant AE sensor so that the time of excitation by the surface pulse due
to the breakage of the glass capillary is equal for both sensors. The measurement setup as well as the
results are described in References [1], [2] and discussed further in Reference [3]. Figure 1 b) holds the
representation of the AE sensor response by the output signal voltage s in time t. The excitation of the
AE sensor is characterized by a rather distinct pulse-like shape, whereas the response of the AE sensor
to the excitation is an oscillating electrical signal with a rather sharp rise till to the maximum amplitude
followed by a less sharp decline. The comparison of both graphs, Figure 1 a) and Figure 1 b), underline
that the excitation of the sensor by a mechanical stimulus (i.e. the surface displacement) differs in
general from its response (i.e. the electrical signal). Only in the exceptional case of a displacement
sensor, the shape of the excitation and the respective response would be similar.

Key
s (t) output signal voltage (arbitrary units) of the broadband capacitive sensor as a function of time t
C
s(t) output signal voltage (arbitrary units) of the resonant AE sensor as a function of time t
Figure 1 — Excitation and response of a piezoelectric sensor in case of a surface pulse according
to reference [2], a) the output signal of the broadband capacitive sensor representing the
excitation and b) the output signal of a resonant AE sensor representing the response
Section 1 of the measurement chain, the AE sensor, provides the mechanical-to-electrical conversion for
burst emission detection and burst signal acquisition as depicted schematically in Figure 2.
Section 2 of the measurement chain, the signal conditioning, commences where the analogue electrical
signal at the sensor output is connected to the input of the impedance adapted preamplifier. The output
signal voltage of the AE sensor is amplified by the preamplifier gain between the lower and the upper
roll-off frequency of the built-in bandpass filter. The output of the preamplifier is capable to drive the
amplified AE signal over some 100 m to the input of the measurement board of the AE instrument
without significant distortion. Section 2 of the measurement chain is concluded when the signal has
passed the analogue filter of the measurement board (including a low-pass anti-aliasing filter).
Section 3 of the measurement chain, the signal acquisition, starts with the analogue-to-digital
conversion, where the analogue signal is converted at a given rate into a sequence of discrete samples.
The sampled signal is then sent to the digital signal processing unit (i.e. digital signal filtering), where
non-relevant frequency contents can be removed in a convenient way by selecting suited low-pass,
high-pass or notch filters when setting up the acquisition process. The main step of section 3 is the
conversion from the digital signal to the burst signal features.

Key
XD piezoelectric sensor, section 1 of the measurement chain
SC signal conditioning, section 2 of the measurement chain
SA signal acquisition, section 3 of the measurement chain
EW elastic wave arriving at the sensitive face of the sensor mounted onto the surface of the test object
ES electrical signal at the sensor output in response to the excitation at the input side
G(f) gain with respect to the frequency f within the bandwidth of the preamplifier
l length of the coaxial cable from the preamplifier output to the measurement board input
T(f) transmission of the high-pass and the low-pass (anti-aliasing) filter with respect to the frequency f
AS analogue signal at the input of the analogue-to-digital conversion
DS digital signal as the result of the analogue-to-digital conversion
s[i] digital signal voltage of sample i measured at time t[i]
DSP digital signal processing utilizing algorithms for low-pass, high-pass and notch filtering
BSF burst signal features as the result of a hit
WF burst signal waveform as the result of a hit
AED acoustic emission data
WFD waveform data
Figure 2 — Principle of the measurement chain for burst signal acquisition
A burst signal is detected when the measured signal voltage exceeds the first time the selected detection
threshold after a defined period without threshold crossings. The event of burst signal detection
constitutes a hit and triggers the determination of burst signal features (e.g. arrival time, measurement
channel number, maximum amplitude, rise time, duration, energy) as well as the registration of
additional information related to continuous signal features (e.g. background noise level). Further
information characteristic of the given conditions at the time of burst signal detection, for instance time
synchronized slow-varying parameter data (e.g. reading of a pressure gauge) acquired at a sampling
rate appropriate for the application and digitized by the AE instrument itself or by a separate measuring
instrument, should be added to the AE data set.
In the course of the data acquisition process for detection and characterization of burst signals, a
stream of AE data sets is generated and stored to the AE data. Optionally, the samples of the burst signal
can be stored as digitized representation for further analysis, what is called waveform recording. In this
case two separate but interrelated data bases are provided as the result of the acquisition process. At
the end of the section 3 of the measurement chain, AE data and waveform data are available for analysis
and output of results, on-line as well as off-line.
5 Piezoelectric Sensor
5.1 General
A piezoelectric sensor is the most commonly used device for detecting acoustic emission (AE). It
provides the most effective conversion of elastic waves into an electrical signal in the frequency range
most commonly used for AE detection, 20 kHz – 1 MHz. Usually, it consists of a piezoelectric ceramic
element mounted in a protective housing. The piezoelectric element is sensitive to different wave types
arriving from any direction at the sensor’s face: compressional, shear, surface (Rayleigh) and plate
(Lamb) waves.
5.2 Sensing element
The sensing material affects the conversion efficiency and operating temperature range. Lead zirconate
titanate (PZT), a ceramic, is the most commonly used materia
...