EN ISO 11265:2025
(Main)Environmental solid matrices - Determination of the specific electrical conductivity (ISO 11265:2025)
Environmental solid matrices - Determination of the specific electrical conductivity (ISO 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 11265:2025)
Dieses Dokument legt ein messtechnisches Verfahren zur routinemäßigen Bestimmung der spezifischen elektrischen Leitfähigkeit in einem wässrigen Extrakt aus Boden, Schlamm, Bioabfall oder Abfall fest. Die Bestimmung wird durchgeführt, um einen Hinweis auf den Gehalt an wasserlöslichen Elektrolyten in einer Probe zu erhalten.
Dieses Dokument ist anwendbar für alle Arten von luftgetrockneten Proben aus Boden, Schlamm, Bioabfall und Abfall.
Matrices solides environnementales - Détermination de la conductivité électrique spécifique (ISO 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 11265:2025)
Ta dokument določa instrumentalno metodo za rutinsko določanje specifične električne prevodnosti v vodnem ekstraktu tal, blata, bioloških odpadkov ali odpadkov. Z določevanjem se ugotavlja vsebnost v vodi topnih elektrolitov v vzorcu. Ta dokument se uporablja za vse vrste vzorcev tal, blata, bioloških odpadkov in odpadkov, sušenih na zraku.
General Information
- Status
- Published
- Publication Date
- 09-Sep-2025
- Technical Committee
- CEN/TC 444 - Environmental characterization
- Drafting Committee
- CEN/TC 444/WG 5 - Physical tests
- Current Stage
- 6060 - Definitive text made available (DAV) - Publishing
- Start Date
- 10-Sep-2025
- Due Date
- 22-Oct-2026
- Completion Date
- 10-Sep-2025
Relations
- Effective Date
- 26-Nov-2025
- Effective Date
- 28-Jan-2026
- Effective Date
- 28-Jan-2026
- Consolidated By
ISO 11265:2025 - Environmental solid matrices — Determination of the specific electrical conductivity - Effective Date
- 12-Feb-2026
Overview
EN ISO 11265:2025 – Environmental solid matrices - Determination of the specific electrical conductivity – is an internationally recognized standard developed by CEN and ISO. It establishes an instrumental method for the routine determination of specific electrical conductivity in aqueous extracts of environmental solid matrices such as soil, sludge, biowaste, and waste.
This standard is applicable to all types of air-dried samples, making it a valuable tool for laboratories and organizations involved in environmental monitoring, soil quality assessment, waste management, and regulatory compliance. The procedure provides reliable data on the content of water-soluble electrolytes within a sample, offering insights into salinity, contamination, and other key environmental parameters.
Key Topics
Scope of Application
- All types of air-dried soil, sludge, biowaste, and waste
- Determination performed on an aqueous extract
- Provides indication of water-soluble electrolyte content
Instrumental Method
- Utilizes a conductivity meter with temperature correction capability
- Requires precise sample preparation and extraction procedures
- Employs calibration using potassium chloride solutions
Sample Preparation
- Guidance on comminuting, drying, and filtering samples to obtain representative sub-samples
- Compliance with referenced standards for sample pretreatment
Measurement Principles
- Ensures measurements are temperature-adjusted to 25 °C
- Addresses interferences such as electrode contamination and air bubbles
Repeatability and Quality Control
- Specifications for repeatability of measurements
- Inclusion of blank determinations to account for background conductivity
Applications
Environmental and Regulatory Testing:
Laboratories use EN ISO 11265:2025 to assess the salinity and ion content of environmental samples. The determination of specific electrical conductivity helps in identifying contamination levels in soils, sludge, and waste, which is critical for:
- Soil Quality Monitoring: Understanding soil health and fertility by measuring salt levels and potential toxicity for agriculture or land management.
- Sludge and Biowaste Evaluation: Supporting waste valorization and safe land application by assessing the presence of soluble salts.
- Waste Characterization: Assisting in the regulatory classification of waste streams and treatment requirements.
- Remediation Projects: Guiding remediation decisions by monitoring changes in soil or waste salinity before, during, and after treatment.
- Compliance Auditing: Satisfying international, national, or local environmental regulations regarding waste and soil management.
The standard’s practical procedure ensures that results are reproducible and comparable across laboratories, promoting consistency in environmental testing and reporting.
Related Standards
The following standards are referenced or otherwise relevant when implementing EN ISO 11265:2025:
- ISO 11464: Soil quality - Pretreatment of samples for physico-chemical analysis
- ISO 7888: Water quality - Determination of electrical conductivity
- EN 13038: Soil improvers and growing media - Determination of electrical conductivity
- EN 15002: Characterization of waste - Preparation of test portions from the laboratory sample
- EN 16179: Sludge, treated biowaste and soil - Guidance for sample pretreatment
- CEN/TS 15937:2013: Superseded by this standard
Summary
EN ISO 11265:2025 provides a standardized, effective approach for determining the specific electrical conductivity of soils, sludge, biowaste, and waste samples. Its widespread adoption not only assists in environmental monitoring and compliance but also supports scientific research, agronomy, and sustainable waste management practices. The systematic methodology outlined in this standard ensures accuracy, consistency, and reliability, thereby enabling sound environmental decision-making.
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Frequently Asked Questions
EN ISO 11265:2025 is a standard published by the European Committee for Standardization (CEN). Its full title is "Environmental solid matrices - Determination of the specific electrical conductivity (ISO 11265:2025)". This standard covers: 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.
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.
EN ISO 11265:2025 is classified under the following ICS (International Classification for Standards) categories: 13.080.20 - Physical properties of soils. The ICS classification helps identify the subject area and facilitates finding related standards.
EN ISO 11265:2025 has the following relationships with other standards: It is inter standard links to CEN/TS 15937:2013, EN 4681-002:2012, CEN/TS 16201:2013, ISO 11265:2025. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
EN ISO 11265:2025 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-marec-2026
Nadomešča:
SIST ISO 11265:1996
SIST ISO 11265:1996/Cor 1:2005
SIST-TS CEN/TS 15937:2013
Trdni matriksi v okolju - Določanje specifične električne prevodnosti (ISO
11265:2025)
Environmental solid matrices - Determination of the specific electrical conductivity (ISO
11265:2025)
Feste Umweltmatrizes - Bestimmung der spezifischen elektrischen Leitfähigkeit (ISO
11265:2025)
Matrices solides environnementales - Détermination de la conductivité électrique
spécifique (ISO 11265:2025)
Ta slovenski standard je istoveten z: EN ISO 11265:2025
ICS:
13.080.20 Fizikalne lastnosti tal Physical properties of soils
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 11265
EUROPEAN STANDARD
NORME EUROPÉENNE
September 2025
EUROPÄISCHE NORM
ICS 13.080.20 Supersedes CEN/TS 15937:2013
English Version
Environmental solid matrices - Determination of the
specific electrical conductivity (ISO 11265:2025)
Matrices solides environnementales - Détermination Feste Umweltmatrizes - Bestimmung der spezifischen
de la conductivité électrique spécifique (ISO elektrischen Leitfähigkeit (ISO 11265:2025)
11265:2025)
This European Standard was approved by CEN on 23 August 2025.
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. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists 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.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11265:2025 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 11265:2025) has been prepared by Technical Committee ISO/TC 190 "Soil
quality " in collaboration with Technical Committee CEN/TC 444 “Environmental characterization of
solid matrices” the secretariat of which is held by NEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by March 2026, and conflicting national standards shall
be withdrawn at the latest by March 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes CEN/TS 15937:2013.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: 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 the
United Kingdom.
Endorsement notice
The text of ISO 11265:2025 has been approved by CEN as EN ISO 11265:2025 without any modification.
International
Standard
ISO 11265
Second edition
Environmental solid matrices —
2025-08
Determination of the specific
electrical conductivity
Matrices solides environnementales — Détermination de la
conductivité électrique spécifique
Reference number
ISO 11265:2025(en) © ISO 2025
ISO 11265:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 11265:2025(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 . 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 . 5
11 Test report . 5
Annex A (informative) Results of an interlaboratory trial for the determination of the specific
electrical conductivity of soils . 6
Bibliography . 7
iii
ISO 11265:2025(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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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, 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.
iv
International Standard ISO 11265:2025(en)
Environmental solid matrices — Determination of the specific
electrical conductivity
1 Scope
This document specifies an instrumental method for the routine determination of the specif
...




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