Foreword

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This document was prepared by Technical Committee ISO/TC 190, Soil quality, Subcommittee SC 3, Chemical and physical characterization, in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/TC 444, Environmental characterization of solid matrices, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This second edition cancels and replaces the first edition ( ISO 11265:1994 ), which has been technically revised. It also incorporates the Technical Corrigendum ISO 11265:1994/Cor 1:1996 .

The main changes are as follows:

change of temperature criteria during extraction;
the distinction between solid and sludge-like matrices is added.

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.

1 Scope

This document specifies an instrumental method for the routine determination of the specific electrical conductivity in an aqueous extract of soil, sludge, biowaste or waste. The determination is carried out to obtain an indication of the content of water-soluble electrolytes in a sample.

This document is applicable to all types of air-dried samples of soil, sludge, biowaste and waste.

2 Normative references

3 Terms and definitions

4 Principle

5 Reagents

5.1

5.2

5.3

5.4

6 Apparatus

6.1

6.2

6.3

6.4

6.5

6.6

6.7

7 Laboratory sample

8 Procedure

8.1 Extraction

8.2 Checking of the cell constant

8.3 Measurement of the electrical conductivity of the filtrates

9 Interferences

9.1

9.2

9.3

10 Repeatability

11 Test report

Bibliography

ISO 11265:2025

Environmental solid matrices. Determination of the specific electrical conductivity

Current

Published:

28 Aug 2025