ISO 24489:2024

International
Standard
ISO 24489
First edition
Non-destructive testing — Acoustic
2024-01
emission testing — Detection of
corrosion at atmospheric and low-
pressure metallic storage tank
floors
Reference number
© ISO 2024
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General principles . 2
5 Qualification of test personnel . 2
6 Test equipment . 2
6.1 Acoustic emission testing system.2
6.2 Acoustic emission sensors .3
6.3 Acoustic emission signal cables .3
6.4 Couplant .3
6.5 Preamplifiers .3
6.6 Power signal cables .3
6.7 Filters .4
6.8 Acoustic emission instrument .4
6.9 Maintenance and verification of test equipment .5
7 Actions before testing . 5
7.1 General information.5
7.2 Documents.5
7.3 Site inspection .5
7.4 Preparation of test instruction and record sheet .5
7.5 Sensor mounting .5
7.6 Setting of the acoustic emission instrument .6
7.6.1 First steps .6
7.6.2 Simulation of acoustic emission sources.6
7.6.3 Determination of sound velocity .6
7.6.4 Background noise .7
7.6.5 Sensitivity check and threshold .7
8 Performing the test . 8
8.1 Storage tank liquid level and condition .8
8.2 Interfering acoustic emission sources .9
8.3 Data acquisition and observations during acoustic emission testing .9
9 Interpretation of test results . 9
9.1 General requirements .9
9.2 Data processing.9
9.3 Classification system for the corrosion status and recommendations for maintenance .10
10 Documentation . 10
10.1 General .10
10.2 Written test instruction .10
10.3 Test records .11
10.4 Test report .11
Annex A (informative) Classification method based on time-difference location analysis and an
example .13
Annex B (informative) Classification method based on overall floor condition analysis and an
example .18
Bibliography .23

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 135, Non-destructive testing, Subcommittee
SC 9, Acoustic emission testing.
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iv
Introduction
Industrial applications of acoustic emission testing for atmospheric metal storage tanks have been gaining
wider usage alongside marked improvement of acoustic emission testing technologies. The effectiveness of
any application of acoustic emission testing depends upon proper and correct use of the acoustic emission
instruments and test techniques.
In addition, existing international acoustic emission standards lack a specification of a classification system
with the associated recommendations for maintenance.
The purpose of this document is to provide requirements for the testing equipment, testing procedures and
classification system for acoustic emission testing for corrosion of atmospheric metal storage tank floors.

v
International Standard ISO 24489:2024(en)
Non-destructive testing — Acoustic emission testing —
Detection of corrosion at atmospheric and low-pressure
metallic storage tank floors
1 Scope
This document describes the testing methodology based on acoustic emission (AE) for atmospheric and low-
pressure (less than or equal to 50 kPa on top of the tank) metallic storage tank floors and the classification
system to be used for test results.
This document applies to acoustic emission testing (AT) for corrosion severity of atmospheric metal storage
tank floors.
The technique is limited to tank floors made of construction steel and relies on an active corrosion process.
It applies only in cases where corrosion of the floor is the governing damage mechanism. Good results will
be obtained providing corrosion conditions have not changed.
2 Normative references
T
...