ISO 15238:2025

International
Standard
ISO 15238
Third edition
Coal — Determination of total
2025-07
cadmium
Charbon — Dosage du cadmium total
Reference number
© ISO 2025
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Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 1
6 Apparatus . 2
7 Preparation of sample . 2
8 Procedure . 3
8.1 Ashing of coal sample .3
8.2 Preparation of test solution .3
8.3 Preparation of blank solution . .3
8.4 Graphite-furnace atomic absorption analysis .3
8.4.1 Calibration . . .3
8.4.2 Measurement of standards .3
8.4.3 Measurement of test solution . .4
8.4.4 Measurement of blank solution .4
9 Expression of results . 4
9.1 Ash mass fraction . .4
9.2 Cadmium mass fraction .4
10 Precision . 5
10.1 Repeatability limit .5
10.2 Reproducibility critical difference .5
11 Test report . 5
Bibliography . 6

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Foreword
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This document was prepared by Technical Committee ISO/TC 27, Coal and coke, Subcommittee SC 5, Methods
of analysis.
This third edition cancels and replaces the second edition (ISO 15238:2016), which has been technically
revised.
The main changes are as follows:
— the normative references have been updated;
— Formulae (1) and (2) have been modified.
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.

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International Standard ISO 15238:2025(en)
Coal — Determination of total cadmium
1 Scope
This document specifies a procedure for the determination of the total cadmium mass fraction of coal.
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 3696, Water for analytical laboratory use — Specification and test methods
ISO 5068-2, Brown coals and lignites — Determination of moisture — Part 2: Indirect gravimetric method for
moisture in the analysis sample
ISO 11722, Solid mineral fuels — Hard coal — Determination of moisture in the general analysis test sample by
drying in nitrogen
ISO 13909-4, Coal and coke — Mechanical sampling — Part 4: Preparation of test samples of coal
ISO 18283, Coal and coke — Manual sampling
3 Terms and definitions
No terms and definitions are listed in this document.
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