SIST EN ISO 11265:2026

Environmental solid matrices - Determination of the specific electrical conductivity (ISO/FDIS 11265:2025)

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.

Feste Umweltmatrizes - Bestimmung der spezifischen elektrischen Leitfähigkeit (ISO/FDIS 11265:2025)

Dieses Dokument legt ein messtechnisches Verfahren zur routinemäßigen Bestimmung der spezifischen elektrischen Leitfähigkeit in einem wässrigen Extrakt aus Boden, Schlamm, Bioabfall und Abfall fest. Die Bestimmung wird durchgeführt, um einen Hinweis auf den Gehalt an wasserlöslichen Elektrolyten in einer Probe zu erhalten.
Dieses Dokument gilt für alle Arten von luftgetrockneten Proben aus Boden, Schlamm, Bioabfall oder Abfall.

Matrices solides environnementales - Détermination de la conductivité électrique spécifique (ISO/FDIS 11265:2025)

Le présent document spécifie une méthode instrumentale pour la détermination en routine de la conductivité électrique spécifique d’un extrait aqueux de sol, de boues, de biodéchets ou de déchets. La détermination est effectuée afin d’obtenir une indication sur la teneur en électrolytes hydrosolubles d’un échantillon.
Le présent document est applicable à tous les types d’échantillons de sols, de boues, de biodéchets et de déchets séchés à l’air.

Trdni matriksi v okolju - Določanje specifične električne prevodnosti (ISO/FDIS 11265:2025)

General Information

• Status: Not Published
• Public Enquiry End Date: 01-Dec-2024
• ICS: 13.080.20 - Physical properties of soils
• Technical Committee: KAT - Soil quality
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 09-Jun-2025
• Due Date: 28-Jul-2025
• Completion Date: 18-Jun-2025
• Ref Project: EN ISO 11265:2025 - Environmental solid matrices - Determination of the specific electrical conductivity (ISO 11265:2025)

Relations

• Replaces: SIST-TS CEN/TS 15937:2013 - Sludge, treated biowaste and soil - Determination of specific electrical conductivity
• Effective Date: 26-Nov-2025
• Revises: SIST ISO 11265:1996/Cor 1:2005 - Soil quality - Determination of the specific electrical conductivity
• Effective Date: 01-Oct-2025
• Revises: SIST ISO 11265:1996 - Soil quality -- Determination of the specific electrical conductivity
• Effective Date: 01-Oct-2025

Overview

SIST EN ISO 11265:2026, titled Environmental Solid Matrices - Determination of the Specific Electrical Conductivity (ISO 11265:2025), is a comprehensive international standard developed by CEN and ISO to define an instrumental method for measuring the specific electrical conductivity in aqueous extracts of environmental solid matrices. This standard is applicable to air-dried samples of soil, sludge, biowaste, and waste materials. By establishing a routine procedure to determine the water-soluble electrolyte content, this standard facilitates consistent, reliable assessment of environmental samples' chemical properties.

The method involves water extraction of the sample at controlled temperature conditions, followed by conductivity measurement of the extract, corrected to 25 °C. SIST EN ISO 11265:2026 offers a reliable metric to evaluate soil quality, sludge treatment effectiveness, and environmental pollution levels through electrolyte concentration monitoring.

Key Topics

• Scope: Routine determination of specific electrical conductivity in aqueous extracts of air-dried soils, sludge, biowaste, and waste.
• Extraction Ratio: 1:5 mass to volume ratio (m/V) of sample to water, extracted at 22 °C ± 3 °C.
• Measurement Principle: Using a conductivity meter with temperature correction to measure electrical conductivity of filtered extracts.
• Sample Preparation: Comminution and pretreatment of samples according to related ISO and EN standards (e.g., ISO 11464, EN 15002).
• Reagents: Use of demineralized water with low intrinsic conductivity; calibration of instruments using potassium chloride solutions of defined molarity.
• Apparatus: Conductivity meter with an adjustable measuring range and temperature correction, shaking machine, glassware, and filtration equipment.
• Accuracy: Instrument cell constants calibrated against potassium chloride standards to ensure measurement reliability within 5% deviation.
• Interferences & Repeatability: Considerations for matrix effects, foreign bodies in samples, and maintaining proper shaking and filtration to achieve consistent results.
• Reporting: Results expressed as specific electrical conductivity corrected to a standard temperature of 25 °C, reported to one decimal place.

Applications

SIST EN ISO 11265:2026 serves multiple practical applications in environmental science, waste management, and agricultural quality control:

• Soil Quality Assessment: Monitoring water-soluble salts which affect soil fertility, plant growth, and contamination levels.
• Waste Characterization: Evaluating the soluble electrolyte content in sludge, biowaste, and other wastes to inform treatment processes and regulatory compliance.
• Environmental Monitoring: Tracking electrolyte concentrations in solid matrices helps detect pollution trends and effects from industrial or agricultural sources.
• Laboratory Standardization: Providing a harmonized method to aid laboratories worldwide in producing comparable data on solid environmental samples.
• Research & Development: Supporting scientific studies on soil chemistry, biodegradation of waste, and environmental remediation effectiveness.

By following this standard, practitioners ensure accuracy, repeatability, and transparency in determining specific electrical conductivity, critical for informed decision-making in environmental management and regulatory frameworks.

Related Standards

To support conformity and comprehensive analysis, SIST EN ISO 11265:2026 references and aligns with several related international and European standards:

• ISO 7888:1985 - Water quality - Determination of electrical conductivity, providing foundational measurement techniques.
• ISO 11464:2006 - Soil quality - Pretreatment of samples for physico-chemical analysis, defining sample handling protocols.
• EN 15002 - Characterization of waste - Preparation of test portions from the laboratory sample, guiding sample subdivision.
• EN 16179 - Sludge, treated biowaste and soil - Guidance for sample pretreatment, outlining methods to prepare solid matrices accurately.
• EN 13038 - Specifically addressing biowaste with particle sizes larger than 10 mm.

These interconnected standards enable laboratories and environmental agencies to execute comprehensive, standardized soil and waste testing regimes, supporting environmental protection initiatives globally.

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Keywords: SIST EN ISO 11265:2026, specific electrical conductivity, aqueous extract, soil testing, sludge analysis, biowaste, waste characterization, environmental solid matrices, conductivity measurement, water-soluble electrolytes, ISO standards, environmental monitoring, sample pretreatment, laboratory method.

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 11265:2024
01-november-2024
Trdni matriksi v okolju - Določanje specifične električne prevodnosti (ISO/DIS
11265:2024)
Environmental solid matrices - Determination of the specific electrical conductivity
(ISO/DIS 11265:2024)
Feste Umweltmatrizes - Bestimmung der spezifischen elektrischen Leitfähigkeit (ISO/DIS
11265:2024)
Matrices solides environnementales - Détermination de la conductivité électrique
spécifique (ISO/DIS 11265:2024)
Ta slovenski standard je istoveten z: prEN ISO 11265
ICS:
13.080.20 Fizikalne lastnosti tal Physical properties of soils
oSIST prEN ISO 11265:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN ISO 11265:2024
oSIST prEN ISO 11265:2024
DRAFT
International
Standard
ISO/DIS 11265
ISO/TC 190/SC 3
Environmental solid matrices —
Secretariat: DIN
Determination of the specific
Voting begins on:
electrical conductivity
2024-09-30
Détermination de la conductivité électrique spécifique
Voting terminates on:
2024-12-23
ICS: 13.080.20
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
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.
Reference number
ISO/DIS 11265:2024(en)
oSIST prEN ISO 11265:2024
DRAFT
ISO/DIS 11265:2024(en)
International
Standard
ISO/DIS 11265
ISO/TC 190/SC 3
Environmental solid matrices —
Secretariat: DIN
Determination of the specific
Voting begins on:
electrical conductivity
Détermination de la conductivité électrique spécifique
Voting terminates on:
ICS: 13.080.20
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2024
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
ISO copyright office
RECIPIENTS OF THIS DRAFT ARE INVITED
CP 401 • Ch. de Blandonnet 8
TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
Phone: [phone]
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 11265:2024(en)
ii
oSIST prEN ISO 11265:2024
ISO/DIS 11265:2024(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 1
6 Apparatus and glassware . 2
7 Laboratory sample . 2
8 Procedure . 3
8.1 Extraction .3
8.2 Checking of the cell constant .3
8.3 Measurement of the electrical conductivity of the filtrates .4
9 Interferences . 4
10 Repeatability . 4
11 Test report . 5
12 Bibliography . 5
Annex A (informative) Results of an interlaboratory trial for the determination of the specific
electrical conductivity of soils . 6

iii
oSIST prEN ISO 11265:2024
ISO/DIS 11265:2024(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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
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 190, Soil quality, Subcommittee SC 3, Chemical
and physical characterization.
This second edition cancels and replaces the first edition (ISO 11265:1994), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— change of temperature criteria during extraction.
— merger with CEN/TS 15937
— the distinction between solid and sludge like matrices is added.
Annex A of this International Standard is for information only.
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
oSIST prEN ISO 11265:2024
DRAFT International Standard ISO/DIS 11265:2024(en)
Environmental solid matrices — Determination of the specific
electrical conductivity
1 Scope
This International Standard specifies an instrumental method for the routine determination of the specific
electrical conductivity in an aqueous extract of soil, sludge, biowaste and waste. The determination is
carried out to obtain an indication of the content of water-soluble electrolytes in a sample.
This International Standard is applicable to all types of air-dried samples of soil, sludge, biowaste and waste.
2 Normative references
The following documents are referred to in the text in such a way that some or all 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 7888:1985, Water quality — Determination of electrical conductivity
ISO 11464:2006, Soil quality — Pretreatment of samples for physico-chemical analysis
EN 15002, Characterization of waste — Preparation of test portions from the laboratory sample
EN 16179, Sludge, treated biowaste and soil — Guidance for sample pretreatment
3 Terms and definitions
No terms and definitions are listed in this document.
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 E
...