SIST EN IEC 61039:2025
(Main)Classification of insulating liquids
Classification of insulating liquids
IEC 61039:2025 establishes the detailed classification of the N family (insulating liquids) that belongs to class L (lubricants, industrial oils and related products) in accordance with ISO 8681 and ISO 6743-99, affecting product categories that include products derived from petroleum processing, synthetic chemical products and synthetic and natural esters.
Klassifizierung der Isolierflüssigkeiten
Classification des liquides isolants
L'IEC 61039:2025 établit la classification détaillée de la famille N (liquides isolants) qui appartient à la classe L (lubrifiants, huiles industrielles et produits connexes) conformément aux normes ISO 8681 et ISO 6743-99, concernant les catégories de produit qui incluent des produits dérivés du traitement du pétrole, les produits chimiques synthétiques et les esters naturels et synthétiques. Ce document s’applique aux liquides neufs. Pour les liquides en service, des essais complémentaires peuvent être exigés pour assurer la conformité à la présente norme.
Splošna klasifikacija izolacijskih tekočin
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-junij-2025
Nadomešča:
SIST EN 61039:2008
Splošna klasifikacija izolacijskih tekočin
Classification of insulating liquids
Klassifizierung der Isolierflüssigkeiten
Classification des liquides isolants
Ta slovenski standard je istoveten z: EN IEC 61039:2025
ICS:
29.040.10 Izolacijska olja Insulating oils
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 61039
NORME EUROPÉENNE
EUROPÄISCHE NORM April 2025
ICS 29.040.10 Supersedes EN 61039:2008
English Version
Classification of insulating liquids
(IEC 61039:2025)
Classification des liquides isolants Klassifizierung der Isolierflüssigkeiten
(IEC 61039:2025) (IEC 61039:2025)
This European Standard was approved by CENELEC on 2025-03-24. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 61039:2025 E
European foreword
The text of document 10/1249/FDIS, future edition 3 of IEC 61039, prepared by TC 10 "Fluids for
electrotechnical applications" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 61039:2025.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2026-04-30
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2028-04-30
document have to be withdrawn
This document supersedes EN 61039:2008 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61039:2025 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60836 NOTE Approved as EN 60836
IEC 60867 NOTE Approved as EN IEC 60867
IEC 61099 NOTE Approved as EN 61099
IEC 62770 NOTE Approved as EN IEC 62770
IEC 63012 NOTE Approved as EN IEC 63012
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60296 - Fluids for electrotechnical applications - Mineral EN IEC 60296 -
insulating oils for electrical equipment
ISO 2592 - Petroleum and related products - Determination of EN ISO 2592 -
flash and fire points - Cleveland open cup method
ISO 8681 - Petroleum products and lubricants -- Method of - -
classification -- Definition of classes
OECD 301 1992 OECD guidelines for the testing of chemicals - - -
Ready Biodegradability
ASTM D240 - Standard test method for heat of combustion of - -
liquid hydrocarbon fuels by bomb calorimeter
IEC 61039 ®
Edition 3.0 2025-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of insulating liquids
Classification des liquides isolants
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.040.10 ISBN 978-2-8327-0162-1
– 2 – IEC 61039:2025 © IEC 2025
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 ISO classification system . 6
5 Classification of electrical insulating liquids . 7
5.1 General . 7
5.2 Class classification . 7
5.3 Category classification . 8
5.4 Identifying code . 8
6 Summarizing outline . 11
Bibliography . 12
Figure 1 – Meaning of all the letters and digits present in the classification of
insulating liquids . 11
Table 1 – Class classification of petroleum products or related products . 7
Table 2 – Examples of classification for different insulating liquids . 10
IEC 61039:2025 © IEC 2025 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CLASSIFICATION OF INSULATING LIQUIDS
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC 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, IEC 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 https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 61039 has been prepared by IEC technical committee 10: Fluids for electrotechnical
applications. It is an International Standard.
This third edition cancels and replaces the second edition published in 2008. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) updating of the classification of insulating liquids, taking into account the largest number
possible of substances that have, or may have, a possible application in electrical
components.
– 4 – IEC 61039:2025 © IEC 2025
The text of this International Standard is based on the following documents:
Draft Report on voting
10/1249/FDIS 10/1258/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IEC 61039:2025 © IEC 2025 – 5 –
INTRODUCTION
WARNING – Health and safety
This document does not purport to address all the safety problems associated with its use. It is
the responsibility of the user of this document to establish appropriate health and safety
practices and determine the applicability of regulatory limitations prior to use.
The insulating liquids which are the subject of this document should be handled with due regard
to personal hygiene. Direct contact with eyes can cause slight irritation. In the case of eye
contact, irrigation with copious quantities of clean running water should be carried out and
medical advice sought.
Some of the tests specified in this document involve the use of processes that could lead to a
hazardous situation. Attention is drawn to the relevant standard for guidance.
WARNING – Environment
This document involves ins
...
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