EN IEC 60480:2019

Specifications for the re-use of sulphur hexafluoride (SF6) and its mixtures in electrical equipment

This document provides criteria for the re-use of sulphur hexafluoride (SF6) and its mixtures after recovery and reclaiming from electrical equipment (e.g. for maintenance, at the end-oflife). Sulphur hexafluoride (SF6), nitrogen (N2) and carbon tetrafluoride (CF4), are gases commonly used for electrical equipment. Taking into account environmental concerns, particular attention is paid to re-use criteria for SF6 and its mixtures with N2 and CF4 for its use in electrical equipment. Procedures for recovering and reclaiming used SF6 and its mixtures are outside the scope of this document and are described in IEC 62271-4. This document provides several annexes on the description of the different methods of analysis, on by-products, on the procedure for evaluating the potential health effects from byproducts, on cryogenic reclaiming of SF6, and on reclaiming recommendations. Storage, transportation and disposal of SF6 and its mixtures are outside the scope of this document and are covered by IEC 62271-4. Procedures to determine SF6 leakages are described in IEC 60068-2-17 [4]1. For the purposes of this document, the complementary gases used in SF6 mixtures will be limited to N2 or CF4.

Spezifikationen für die Wiederverwendung von Schwefelhexafluorid (SF6) und seinen Mischungen in elektrischen Betriebsmitteln

Spécifications pour la réutilisation de l’hexafluorure de soufre (SF6) et des mélanges contenant du SF6 dans le matériel électrique

Le présent document spécifie des critères de réutilisation de l’hexafluorure de soufre (SF6) et des mélanges contenant du SF6 après reprise et régénération depuis le matériel électrique(par exemple, pour la maintenance ou en fin de vie). L’hexafluorure de soufre (SF6), l’azote (N2) et le tétrafluorure de carbone (CF4) sont des gaz communément utilisés pour le matériel électrique. Une attention particulière est accordée aux critères de réutilisation du SF6 et de ses mélanges avec N2 et CF4 pour leur utilisation dans le matériel électrique, afin de prendre en compte les aspects d’environnement. Les procédures de reprise et de régénération du SF6 usagé et des mélanges contenant du SF6 usagé ne relèvent pas du domaine d’application du présent document. Elles sont décrites dans l’IEC 62271-4. Le présent document comprend plusieurs annexes qui décrivent les différentes méthodes d’analyse, traitent des sous-produits, de la procédure d’évaluation des effets potentiels des sous-produits sur la santé, de la régénération cryogénique du SF6 et donnent des recommandations relatives à la régénération. Les procédures de stockage, de transport et d’élimination du SF6 et des mélanges contenant du SF6 ne relèvent pas du domaine d’application du présent document. Elles sont décrites dans l’IEC 62271-4. Les procédures de détermination des fuites de SF6 sont décrites dans l’IEC 60068-2-17 [4]1. Pour les besoins du présent document, les gaz complémentaires utilisés dans les mélanges du SF6 sont limités à l’azote (N2) ou au tétrafluorure de carbone (CF4).

Specifikacija za ponovno uporabo žveplovega heksafluorida(SF6) in njegovih mešanic v električni opremi

Ta dokument vsebuje merila za ponovno uporabo žveplovega heksafluorida (SF6) in njegovih mešanic po predelavi in ponovnem pridobivanju iz električne opreme (npr. za vzdrževanje, ob koncu življenjske dobe). Žveplov heksafluorid (SF6), dušik (N2) in ogljikov tetrafluorid (CF4) so plini, ki se običajno uporabljajo za električno opremo. Ob upoštevanju okoljskih vprašanj je posebna pozornost namenjena kriterijem ponovne uporabe SF6 in njegovih mešanic z N2 in CF4 za njegovo uporabo v električni opremi. Postopki za predelavo in ponovno pridobivanje uporabljenega SF6 in njegovih mešanic ne spadajo na področje uporabe tega dokumenta in so opisani v standardu IEC 62271-4.
Ta dokument vsebuje več dodatkov o opisu različnih metod analize, stranskih proizvodih, postopku ocenjevanja možnih vplivov na zdravje iz stranskih proizvodov, kriogenem ponovnem pridobivanju SF6 in priporočilih za ponovno pridobivanje.
Shranjevanje, prevoz in odstranjevanje SF6 ter njegovih mešanic ne spadajo na področje uporabe tega dokumenta in so opisani v standardu IEC 62271-4. Postopki za določanje puščanja SF6 so opisani v standardu IEC 60068-2-17 [4]1.
V tem dokumentu so plini, uporabljeni v mešanicah SF6, omejeni na N2 ali CF4.

General Information

• Status: Published
• Publication Date: 23-May-2019
• Withdrawal Date: 08-May-2022
• ICS: 29.040.20 - Insulating gases
• ICS: 29.130 - Switchgear and controlgear
• ICS: 29.130.01 - Switchgear and controlgear in general
• Technical Committee: CLC/SR 10 - Fluids for electrotechnical applications
• Drafting Committee: IEC/TC 10 - IEC_TC_10
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 24-May-2019
• Completion Date: 24-May-2019
• Ref Project: SIST EN IEC 60480:2019 - Specification for re-use of SF6 and its mixtures in electrical equipment

Relations

• Replaces: EN 60480:2004 - Guidelines for the checking and treatment of sulphur hexafluoride (SF6) taken from electrical equipment and specification for its re-use
• Effective Date: 28-May-2019

Overview

EN IEC 60480:2019 (IEC 60480:2019) specifies criteria for the re‑use of sulphur hexafluoride (SF6) and its permitted mixtures (limited to N2 and CF4) after recovery and reclaiming from electrical equipment. The standard focuses on quality, contamination, health and safety, and analytical verification that recovered SF6 or SF6‑mixtures meet re‑use requirements for electrical equipment. Procedures for the actual recovery/reclaiming processes are covered by IEC 62271‑4, and storage/transport/disposal follow that same reference.

Keywords: EN IEC 60480:2019, SF6 re‑use, sulphur hexafluoride, SF6 mixtures, reclaiming, electrical equipment

Key topics and technical requirements

• Scope and applicability: Re‑use criteria for recovered SF6 and SF6/N2 or SF6/CF4 mixtures used in maintenance or end‑of‑life commissioning of electrical equipment.
• Contaminants and sources: Identification of contaminants introduced during handling, operation, internal arcs, and decomposition products.
• By‑products and health evaluation: Behaviour and physiological effects of SF6 decomposition products; procedures to evaluate potential health risks from by‑products.
• Specifications for re‑use: Formal acceptance criteria and decision flow chart for returning recovered gas to service (detailed in tables within the standard).
• Reclaiming feasibility and methods: Guidance on whether reclaiming is practical and on detection techniques to check gas quality.
• Analytical methods: On‑site and laboratory techniques (e.g., gas chromatography, infrared spectroscopy), sampling procedures and recommended test methods (Annex A).
• Cryogenic reclaiming & reclaiming recommendations: Informative annexes describing cryogenic processes and practical reclaiming practices.
• Safety & environment: PPE, first aid, measures for abnormal releases (fires, internal arcs), and environmental aspects. Leak detection is referenced to IEC 60068‑2‑17.

Practical applications

• Utilities and grid operators assessing whether recovered SF6 can be safely re‑used in switchgear and high‑voltage equipment.
• Manufacturers of switchgear and insulating gas systems defining acceptance criteria for returned gas.
• Service contractors, maintenance teams and reclaiming companies that analyze, certify and return SF6 to service.
• Environmental compliance and asset‑management teams implementing SF6 lifecycle and emissions reduction strategies.

Who should use this standard

• Electrical equipment manufacturers, testing laboratories, reclamation contractors, utility asset managers, and health & safety officers involved in SF6 handling and reuse.

Related standards

• IEC 62271‑4 - Handling procedures for SF6 and its mixtures (recovery/reclaiming, storage/transport)
• IEC 60068‑2‑17 - Procedures to determine SF6 leakages

EN IEC 60480:2019 provides the technical framework and analytical requirements needed to support safe, compliant re‑use of SF6 gas, enabling cost‑effective recycling while addressing environmental and health concerns.

Standards Content (Sample)

SLOVENSKI STANDARD
01-september-2019
Nadomešča:
SIST EN 60480:2005
Specifikacija za ponovno uporabo žveplovega heksafluorida(SF6) in njegovih
mešanic v električni opremi
Specification for re-use of SF6 and its mixtures in electrical equipment
Ta slovenski standard je istoveten z: EN IEC 60480:2019
ICS:
29.040.20 Izolacijski plini Insulating gases
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60480

NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2019
ICS 29.130.01; 29.040.20 Supersedes EN 60480:2004
English Version
Specifications for the re-use of sulphur hexafluoride (SF ) and its
mixtures in electrical equipment
(IEC 60480:2019)
Spécifications pour la réutilisation de l'hexafluorure de Spezifikationen für die Wiederverwendung von
soufre (SF ) et des mélanges contenant du SF dans le Schwefelhexafluorid (SF ) und seinen Mischungen in
6 6 6
matériel électrique elektrischen Betriebsmitteln
(IEC 60480:2019) (IEC 60480:2019)
This European Standard was approved by CENELEC on 2019-05-09. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey 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
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60480:2019 E
European foreword
The text of document 10/1075/FDIS, future edition 3 of IEC 60480, prepared by IEC/TC 10 "Fluids for
electrotechnical applications" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 60480:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-02-09
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-05-09
document have to be withdrawn
This document supersedes EN 60480:2004.
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.

Endorsement notice
The text of the International Standard IEC 60480:2019 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 standards
indicated:
IEC 60079-29-2 NOTE Harmonized as EN 60079-29-2
IEC 62271-203 NOTE Harmonized as EN 62271-203
IEC 60376 NOTE Harmonized as EN IEC 60376
IEC 60068-2-17 NOTE Harmonized as EN 60068-2-17

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.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-192 -  International electrotechnical vocabulary - Part 192: - -
Dependability
IEC 60050-212 -  International Electrotechnical Vocabulary - Part 212: - -
Electrical insulating solids, liquids and gases
IEC 60050-441 -  International Electrotechnical Vocabulary. - -
Switchgear, controlgear and fuses
IEC 60050-826 -  International Electrotechnical Vocabulary - Part 826: - -
Electrical installations
IEC 62271-4 2013 High-voltage switchgear and controlgear - Part 4: EN 62271-4 2013
Handling procedures for sulphur hexafluoride (SF6)
and its mixtures
IEC 60480 ®
Edition 3.0 2019-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Specifications for the re-use of sulphur hexafluoride (SF ) and its mixtures
in electrical equipment
Spécifications pour la réutilisation de l’hexafluorure de soufre (SF )
et des mélanges contenant du SF dans le matériel électrique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.040.20; 29.130.01 ISBN 978-2-8322-6697-7

– 2 – IEC 60480:2019 © IEC 2019
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Contaminants and their sources . 9
4.1 General . 9
4.2 Contaminants from handling and use . 9
4.3 SF by-products in equipment that only have an insulating function . 9
4.4 SF by-products in switching equipment . 10
4.5 SF by-products from internal arcs . 10
4.6 SF mixtures specific by-products . 10
5 Specifications for re-use of SF . 10
6 Specifications for re-use of SF mixtures . 11
7 Reclaiming of SF and SF mixtures . 11
6 6
7.1 Feasibility and process . 11
7.2 Detection techniques for checking the quality of the gases. 14
7.2.1 General . 14
7.2.2 On-site analysis . 14
7.2.3 Laboratory analysis . 15
8 Handling, storage and transportation (informative) . 16
9 Safety and first aid . 16
9.1 General safety rules . 16
9.1.1 General . 16
9.1.2 Protection of personnel . 17
9.1.3 Handling of contaminated safety equipment and tools . 18
9.1.4 Pressurized equipment and tools or measuring devices . 19
9.1.5 Personal safety and protective equipment . 19
9.1.6 Facilities and services . 20
9.2 Additional safety measures in case of abnormal release of SF due to
external fire or internal arc fault . 20
9.3 First aid equipment and treatment . 21
9.3.1 General . 21
9.3.2 Irritation of the skin . 21
9.3.3 Irritation of the eyes . 22
9.3.4 Breathing difficulty . 22
10 Environmental aspects . 22
Annex A (informative) Description of methods of analysis (on-site and laboratory) . 23
A.1 Sampling. 23
A.1.1 General . 23
A.1.2 On-site sampling connection . 23
A.1.3 Sample cylinder for laboratory analysis . 23
A.1.4 Sampling methods for laboratory analysis . 24
A.2 On-site analysis . 25
A.2.1 General . 25
A.2.2 SF concentration meter . 25
IEC 60480:2019 © IEC 2019 – 3 –
A.2.3 Hygrometers . 25
A.3 Laboratory analysis . 26
A.3.1 Gas chromatography . 26
A.3.2 Infrared spectroscopy . 28
Annex B (informative) By-products of SF6 and its mixtures . 31
B.1 Decomposition of SF and its mixtures . 31
B.1.1 General . 31
B.1.2 Behaviour of SF in an electric arc . 31
B.1.3 SF6 decomposition with low current discharges . 33
B.1.4 Catalytic decomposition of SF (high-temperature behaviour) . 33
B.2 Corrosion behaviour of SF and its by-products . 33
B.3 Measures for the removal of by-products . 33
B.4 Physiological characteristics of by-products . 34
Annex C (informative) Procedures for evaluating the potential effects on health from
by-products of SF and its mixtures . 35
C.1 General . 35
C.2 Formation and health effects of SF by-products . 35
C.2.1 Formation of SF by-products . 35
C.2.2 Effects of SF by-products on health . 36
C.2.3 Quantitative estimation of gaseous by-products . 37
C.2.4 Procedures for health risk evaluation . 38
C.3 Conclusion . 40
Annex D (informative) Reclaiming recommendations . 42
D.1 General . 42
D.2 Filtering recommendations . 42
D.3 Transport of used SF in gas cylinders and containers by road . 42
Annex E (informative) Cryogenic reclaiming of SF . 43
E.1 General . 43
E.2 Applications . 43
E.3 Physical background . 43
E.4 Cryogenic processes. 44
E.5 Description of a cryogenic reclaimer . 44
Bibliography . 47

Figure 1 – Decision flow chart for recovered SF . 13
Figure A.1 – One-sampling cylinder method set-up . 24
Figure A.2 – Two-sampling cylinder method set-up . 24
Figure A.3 – Example of a gas chromatogram in one print out showing the different
possible by-products after decomposition . 27
Figure A.4 – Typical GCMS chromatogram of decomposed SF /CF mixture . 28
6 4
Figure A.5 – IR spectrum of contaminated SF . 30
Figure C.1 – Procedure for the evaluation of the potential effects on health due
to arcing . 39
Figure C.2 – Procedure for the evaluation of the potential effects on health due to low
energy discharges . 40
Figure D.1 – Saturated vapour pressure of various gases as a function of temperature. 43
Figure D.2 – Typical cryogenic reclaimer for SF recovery on site . 45
Figure D.3 – Typical cryogenic reclaimer for removing contaminants . 45

– 4 – IEC 60480:2019 © IEC 2019

Table 1 – SF contaminants . 9
Table 2 – Specifications for re-use of SF . 10
Table 3 – Specifications for re-use of SF /N mixtures . 11
6 2
Table 4 – Specifications for re-use of SF /CF mixtures . 11
6 4
Table 5 – General contaminants and methods for their removal . 12
Table 6 – Typical adsorbents for various SF contaminants . 12
Table 7 – On-site methods . 15
Table 8 – Laboratory methods . 16
Table 9 – Measures when working with SF electric power equipment . 17
Table 10 – Safety measures when opening or accessing gas compartments . 18
Table 11 – Neutralizing solutions . 19
Table 12 – Additional safety measures . 21
Table A.1 – Peak absorption of SF and contaminants . 29
Table C.1 – OELs for SO2, HF, and S2F10 . 37
Table C.2 – SOF production rate . 37
IEC 60480:2019 © IEC 2019 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SPECIFICATIONS FOR THE RE-USE OF SULPHUR HEXAFLUORIDE (SF )
AND ITS MIXTURES IN ELECTRICAL EQUIPMENT

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,
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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
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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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.
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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
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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) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60480 has been prepared by IEC technical committee 10: Fluids
for electrotechnical applications.
This third edition cancels and replaces the second edition, published in 2004. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• specifications for the re-use of SF have been confirmed;
• specifications for the re-use of SF mixtures, namely SF /N and SF /CF mixtures are
6 6 2 6 4
included;
• as a result of a new repartition of annexes in IEC 60376, IEC 60480 and IEC 62271-4, this
new edition now contains the following five annexes:
– Annex A: Description of methods of analysis (on-site and laboratory);
– Annex B: By–products of SF and its mixtures;
– 6 – IEC 60480:2019 © IEC 2019
– Annex C: Procedure for evaluating the potential effects on health from by-products of SF
and its mixtures;
– Annex D: Reclaiming recommendations.
– Annex E: Cryogenic reclaiming of SF ;
The text of this International Standard is based on the following documents:
FDIS Report on voting
10/1075/FDIS 10/1080/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
IEC 60480:2019 © IEC 2019 – 7 –
SPECIFICATIONS FOR THE RE-USE OF SULPHUR HEXAFLUORIDE (SF )
AND ITS MIXTURES IN ELECTRICAL EQUIPMENT

1 Scope
This document provides criteria for the re-use of sulphur hexafluoride (SF ) and its mixtures
after recovery and reclaiming from electrical equipment (e.g. for maintenance, at the end-of-
life).
Sulphur hexafluoride (SF ), nitrogen (N ) and carbon tetrafluoride (CF ), are gases commonly
6 2 4
used for electrical equipment. Taking into account environmental concerns, particular
attention is paid to re-use criteria for SF and its mixtures with N and CF for its use in
6 2 4
electrical equipment. Procedures for recovering and reclaiming used SF and its mixtures are
outside the scope of this document and are described in IEC 62271-4.
This document provides several annexes on the description of the different methods of
analysis, on by-products, on the procedure for evaluating the potential health effects from by-
products, on cryogenic reclaiming of SF , and on reclaiming recommendations.
Storage, transportation and disposal of SF and its mixtures are outside the scope of this
document and are covered by IEC 62271-4. Procedures to determine SF leakages are
described in IEC 60068-2-17 [4] .
mixtures will be
For the purposes of this document, the complementary gases used in SF
limited to N or CF .
2 4
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.
IEC 60050-192, International Electrotechnical Vocabulary – Part 192: Dependability (available
at http://www.electropedia.org)
IEC 60050-212, International Electrotechnical Vocabulary – Part 212: Electrical insulating
solids, liquids and gases (available at http://www.electropedia.org)
IEC 60050-441, International Electrotechnical Vocabulary – Part 441: Switchgear, controlgear
and fuses (available at http://www.electropedia.org)
IEC 60050-826, International Electrotechnical Vocabulary – Part 826: Electrical installations
(available at http://www.electropedia.org)
IEC 62271-4:2013, High-voltage switchgear and controlgear – Part 4: Handling procedures for
sulphur hexafluoride (SF ) and its mixtures
___________
Numbers in square brackets refer to the bibliography.

– 8 – IEC 60480:2019 © IEC 2019
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-192,
IEC 60050-212, IEC 60050-441 and IEC 60050-826, and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
electrical equipment
item used for such purposes as generation, conversion, transmission, distribution or utilization
of electrical energy, such as electric machines, transformers, switchgear and controlgear,
measuring instruments, protective devices, wiring systems, current-using equipment,
insulated bushings, surge arresters
[SOURCE: IEC 60050-826:2004, 826-16-01, modified – "insulated bushings, surge arresters"
has been added.]
3.2
container
vessel (cylinder) suitable for the containment of pressurized gases either in gaseous or liquid
phase, according to local and/or international safety and transportation regulations
3.3
used sulphur hexafluoride
SF which has been introduced into electrical equipment
3.4
reclaiming
process of contaminants removal from an insulating liquid or gas
3.5
recovery
process of transferring gas from electrical equipment to an alternate container
3.6
SF mixture
gas mixture formed by SF and a complementary gas, typically N or CF
6 2 4
3.7
contaminant
foreign substance or material in an insulating liquid or gas which usually has a deleterious
effect on one or more properties
[SOURCE: IEC 60050-212:2010, 212-17-27, modified – "or solid" has been deleted.]
3.8
by-products
contaminants which are formed by the degradation of SF and its mixtures by electrical arcs
or sparks
3.9
ambient air
normal atmosphere surrounding the equipment

IEC 60480:2019 © IEC 2019 – 9 –
[SOURCE: IEC 60079-29-2:2015, 3.1.1]
4 Contaminants and their sources
4.1 General
SF recovered from electrical equipment in operation contains several kinds of contaminants.
Contaminants in recovered SF come both from gas handling and from use.
Table 1 summarizes the main contaminants and their sources. Additional information is
available in Annex B.
contaminants
Table 1 – SF
SF situation and use Origin Possible contaminant

Leaks and incomplete evacuation For pure SF : Air, oil, H O
6 2
Handling and in service
Desorption For SF mixtures: Air, oil, H O, N CF
6 2 2, 4
Gaseous by-products: HF, SO , SOF ,
2 2
SOF SO F
Partial discharges (e.g. corona) and low 4, 2 2
Insulating function
energy flashovers and sparkovers
For SF mixtures: HF, SO , SOF SOF
6 2 2, 4,
SO F , NO , NF
2 2 x X
Gaseous by-products: HF, SO , SOF ,
2 2
SOF , SO F , SF , CF WF
4 2 2 4 4, 6
Solid by-products: Metal dusts, particles,
Switching arc erosion
AlF , FeF WO CuF
Switching equipment 3 3, 3, 2
For SF mixtures: HF, SO , SOF , SOF ,
6 2 2 4
SO F NO , NF
2 2, x X
Mechanical erosion Metal dusts, particles
Gaseous by-products: HF, SO , SOF ,
2 2
SOF , SO F , SF , CF , WF
4 2 2 4 4 6
Solid by-products: Metal dusts, particles,
Internal arc Melting and decomposition of materials
AlF , FeF , WO , CuF
3 3 3, 2
For SF mixtures: HF, SO , SOF , SOF ,
6 2 2 4
SO F , NO , NF
2 2 x X
4.2 Contaminants from handling and use
Filling and recovering gas leads to the additional contamination with ambient air and water
(humidity).
Moisture desorbs from internal surfaces of the equipment and from polymeric parts. Oil from
handling equipment (pumps and compressors) may also be inadvertently introduced.
When using gas mixtures, the possibility of cross contamination shall be considered
(contaminating one gas mixture by another).
4.3 SF by-products in equipment that only have an insulating function
The essential process is the decomposition of SF by partial discharges (e.g. corona) and low
energy flashovers and sparkovers. The immediate products are fragments of SF , such as
SF , SF and F, combining with O and H O to form compounds, mainly HF, SO , SOF ,
5 4 2 2 2 2
SOF and SO F . Due to low energy of the partial discharges, flashovers or sparkovers, the
4 2 2
accumulated quantities of these compounds are usually negligible.

– 10 – IEC 60480:2019 © IEC 2019
4.4 SF by-products in switching equipment
During current interruption, the existence of high temperature arcs leads to the formation of
by-products of SF , vaporized electrode metal, polymeric materials and contaminants. In
addition, chemical reactions take place among the products formed (see Table 1).
The quantity of these by-products depends on the number of operations, the cumulative short
circuit current, the design of equipment and the use of adsorbers (solid adsorbents).
Switching equipment may also contain particles and metal dust coming from the rubbing of
contacts.
4.5 SF by-products from internal arcs
The occurrence of an internal arc is extremely rare. The expected contaminants in SF in
faulted equipment are similar to those normally found in switching equipment. The difference
lies in the quantity of compounds, which create a potential toxic risk (see Clause 9). In
addition, significant vaporization of metallic material occurs and creates additional reaction
products such as dust.
4.6 SF mixtures specific by-products
For SF mixtures, the usual SF by-products mentioned in Table 1 and specific mixture by-
6 6
products, such as nitrogen oxide(s) and nitrogen fluoride(s) for SF /N and fluorocarbon(s) for
6 2
SF /CF , are produced. The quantities depend on the mixture composition, contaminants and
6 4
energy introduced. For typical SF mixtures, the gas decomposition rates are not expected to
exceed those for SF .
Within the by-products generated in mixtures, SF by-products are generally predominant in
terms of quantity and toxicity. Safety procedures related to the presence of the usual SF by-
products shall also apply in applications with SF mixtures.
5 Specifications for re-use of SF
Table 2 – Specifications for re-use of SF
a
Substance Concentration
SF > 97 % volume
Air and/or CF < 30 000 µl/l (i.e. 3 % volume)
H O < 200 µl/l (i.e. 200 ppmv)
b
Mineral oil < 10 mg/kg (i.e. 10 ppmw)
< 50 µl/l total (i.e. 50 ppmv) or 12 µl/l (i.e. 12 ppmv) for (SO +SOF ) or
2 2
Acidity
25 µl/l (i.e. 25 ppmv) HF
Key
ppmv = part per million by volume
ppmw = part per million by weight
a
H S and CO have been considered irrelevant due to lack of valuable data.
b
If gas handling equipment (pump, compressor) containing oil is used, it may be necessary to measure the oil
content of the SF . If all equipment in contact with the SF is oil-free, then it is not necessary to measure the
6 6
oil content.
For the determination of total acidity, the sum of all acidic compounds is reported as one
value. Alternatively, total acidity can be measured in terms of (SO + SOF ) or in terms of HF
2 2
with a limit value of 12 µl/l and 25 µl/l respectively.

IEC 60480:2019 © IEC 2019 – 11 –
6 Specifications for re-use of SF mixtures
Table 3 – Specifications for re-use of SF /N mixtures
6 2
Substance Concentration
N As per OEM specifications
a
SF percentage ±5 % volume of the specified percentage
a
Air and CF < 30 000 µl/l (i.e. 3 % volume)
H O < 200 µl/l (.i.e. 200 ppmv)
b
Mineral oil < 10 mg/kg (i.e. 10 ppmw)
Total acidity < 50 µl/l total (i.e. 50 ppmv) or 12 µl/l (i.e. 12 ppmv) for
(SO +SOF ) or 25 µl/l (i.e. 25 ppmv) HF
2 2
Storage conditions
Shall comply with IEC 62271-4:2013, Clause J.7 in order to prevent liquefaction of SF .
Key
ppmv = part per million by volume
ppmw = part per million by weight
a
Or unless otherwise specified by the original equipment manufacturer (OEM).
b
If gas handling equipment (pump, compressor) containing oil is used, it may be necessary to measure the oil
content of the SF . If all equipment in contact with the SF is oil-free, then it is not necessary to measure the
6 6
oil content.
Table 4 – Specifications for re-use of SF /CF mixtures
6 4
Substance Concentration
CF As per OEM specifications
a
SF percentage ±5 % volume of the specified percentage
a
Air and N < 30 000 µl/l (i.e. 3% volume)
H O < 200 µl/l (.i.e. 200 ppmv)
b
Mineral oil < 10 mg/kg (i.e. 10 ppmw)
Total acidity < 50 µl/l total (i.e. 50 ppmv) or 12 µl/l (i.e. 12 ppmv) for
(SO +SOF ) or 25 µl/l (i.e. 25 ppmv) HF
2 2
Storage conditions
Shall comply with IEC 62271-4:2013, Clause J.7 in order to prevent liquefaction of SF .
Key
ppmv = part per million by volume
ppmw = par per million by weight
a
Or unless otherwise specified by the original equipment manufacturer (OEM).
b
If gas handling equipment (pump, compressor) containing oil is used, it may be necessary to measure the oil
content of the SF . If all equipment in contact with the SF is oil-free, then it is not necessary to measure the
6 6
oil content.
7 Reclaiming of SF and SF mixtures
6 6
7.1 Feasibility and process
The quality of reclaimed SF shall meet the requirements of this document.
– 12 – IEC 60480:2019 © IEC 2019
All occurring contaminants are formed in normal operation and can generally be eliminated
on-site. Table 5 lists methods recommended for removing the contaminants as given in
Table 1.
Table 5 – General contaminants and methods for their removal
Gaseous by- Solid by-
Contaminant Humidity Air, N , CF Mineral oil
2 4
products products
(water vapour)
Removal method Adsorption with Adsorption with Retaining with Separation by Adsorption with
molecular sieve activated solid filters cryogenic activated
aluminium oxide process or charcoal filter
membrane
filtration
For SF and its mixtures, these gaseous contaminants cannot be removed easily on-site. In each situation, an
evaluation of the reclaiming options should be done to determine if the SF and its mixture could be reclaimed
on-site.
Various types of adsorbent materials are available to remove contaminants from SF gas
(see Table 6).
Table 6 – Typical adsorbents for various SF contaminants
Adsorbent Contaminants removed
Molecular sieve 4A Water, SO , SOF , SF
2 2 4
Molecular sieve 13X Water, SO , SOF , SF
2 2 4
(also adsorbs some SF )
Activated aluminium oxide Water, SO , SOF , SF , HF
2 2 4
Soda lime (CaO-NaOH) Water, SO F , HF
2 2
Activated charcoal Oil vapour
If the results of the gas analysis exceed the specifications for re-use of SF and its mixtures
given in Table 2, Table 3 or Table 4, a decision regarding the reclaiming method has to be
made depending on the level and type of contamination. In general, re-purifying the gas on-
site with a service device plus a separation device will be the most favourable way. However,
if re-use is not possible, reclaiming by the gas manufacturer or disposal will be necessary. In
this case, the gas shall be sent to the SF manufacturer or reclaimer.
Figure 1 defines the selection procedure to determine the best use of SF after recovery for
potential treatment.
IEC 60480:2019 © IEC 2019 – 13 –

Figure 1 – Decision flow chart for recovered SF
• For contaminants of water or by-products, the question of whether the SF is reclaimable
on-site depends only on the performance of the filters available. The addition of external
pre-filters may be required to increase the efficiency of the reclaiming process. If the SF
is not reclaimable on-site, then it shall be returned to the SF manufacturer or sent to a
reclaiming or disposal company.
• The case of contamination with air, N and/or CF shall be considered separately.
2 4
• For non-mixed SF , if the concentration of air and/or CF exceeds the maximum
6 4
acceptable contaminant level as given in Table 2, and if the container from which the
sample has been taken contains liquid SF , then transfer SF from the gas phase into a
6 6
second container. The transfer should be continued until a sample from the first reservoir
satisfies the maximum acceptable level. The contents of the second container cannot be

– 14 – IEC 60480:2019 © IEC 2019
reclaimed on-site. Any container that contains no liquid SF , i.e. only the gas phase,
requires the analysis of only one sample for air and CF to determine if it is suitable for re-
use or cannot be reclaimed on-site.
• For mixed SF , if the concentration of air, N and/or CF exceeds the maximum
6 2 4
acceptable contaminant level as given in Table 3 or Table 4, an evaluation of the
reclaiming options should be done to determine if the mixture could be reclaimed on-site.
7.2 Detection techniques for checking the quality of the gases
7.2.1 General
The detection techniques shall be used on gas samples. Details of the procedures for
obtaining a sample and of the analytical methods are provided in Annex A.
7.2.2 On-site analysis
If on-site analysis systems are used, they shall be equipped with a gas recovery system. The
into the atmosphere shall be avoided and the safety of personnel shall be
release of SF
ensured. On-site available analytical methods are shown respectively in Table 7 and Annex A.
In case of high concentration of by-products (see Clause 4), care should be taken to avoid
damage to the measuring instrument.

IEC 60480:2019 © IEC 2019 – 15 –
Table 7 – On-site methods
Substance Detection technique
Portable gas chromatography with thermal conductivity detector (GC-TCD)
Infrared absorption
SF
Condensation method
Speed of sound method
Portable gas chromatography with thermal conductivity detector (GC-TCD)
N in SF mixture Infrared absorption (NOTE 1)
2 6
Speed of sound method (NOTE 1) (NOTE 2)
Portable gas chromatography with thermal conductivity detector (GC-TCD)
CF in SF mixture Infrared absorption
4 6
Speed of sound method (NOTE 1) (NOTE 2)
Portable gas chromatography with thermal conductivity detector (GC-TCD)
By-products:
Infrared absorption
SO , SOF , SO F
2 2 2 2
Electrochemical sensor
Infrared absorption
HF
Electrochemical sensor
Density meter (for the % of SF )
Air and CF Portable gas chromatography with thermal conductivity detector (GC-TCD) (NOTE 3)
Infrared absorption
Electronic hygrometer
Chilled mirror hygrometer
Water (humidity)
Infrared absorption
Electrochemical sensor
Mineral oil Tube for mineral oil
NOTE 1 Indirect quantification done by the subtraction of the SF content.
NOTE 2 Applicable only to known mixture composition.
NOTE 3 Gas chromatography is only used to determine the concentration of N or CF in SF mixtures.
2 4 6
7.2.3 Laboratory analysis
If no equipment is available on-site, the following recommended techniques should be used
(see Table 8). Laboratory methods are intended to provide a quantitative assessment of the
contaminants in a gas sample.
Water is the only contaminant that cannot be determined accurately from a sampling cylinder.
The water content of a sample in a cylinder taken from a container is not representative of the
water content in the container because water adsorbs on all surfaces. Therefore, the water
analysis shall always be carried out directly on the container on-site. There is no recom-
mended order of analysis.
– 16 – IEC 60480:2019 © IEC 2019
Table 8 – Laboratory methods
Contaminants Methods available
SF Gas chromatograph (NOTE 2). Infrared absorption
N in gas mixture Gas chromatograph (NOTE 2)
CF in gas mixture Gas (NOTE 2). Infrared absorption
Air: oxygen and nitrogen Gas chromatograph (NOTE 2)
CF Gas chromatograph (NOTE 2). Infrared absorption
as contaminant
Infrared absorption
Oil
Gas chromatograph (NOTE 2)
Gas chromatograph (NOTE 2)
Decomposition products (total acidity): Ion chromatography
SO , SOF , SO F , SF , HF (NOTE 1) Infrared absorption
2 2 2 2 4
Wet chemistry
NOTE 1 Ion chromatography, infrared absorption and wet chemistry are the only methods available to quantify
HF.
NOTE 2 Gas chromatography can be performed by using adequate detectors for the determination of
contaminants or to control the mixing gas concentrations.

More information about reclaiming recommendations can be found in Annex D. Information
about cryogenic reclaiming, an example of reclaiming technique, can be found in Annex E.
8 Handling, storage and transportation (informative)
Refer to IEC 62271-4.
9 Safety and first aid
9.1 General safety
...