ABB HD4/R - 11. Instructions for handling apparatus containing SF6 gas

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11. Instructions for handling apparatus
containing SF
6
gas
Initspurestate,SF
6
isanodourless,colourless,non-toxicgas
with a density about six times higher than that of air. For this
reason, although it does not lead to any specific physiologi-
caleffects,itcanproduceeffectscausedbylackofoxygenin
places saturated with SF
6
.
The electric arc produced during the interruption phase of the
circuit breaker decomposes a very small amount of SF
6
. The
products of this decomposition remain inside the poles and are
absorbed by special substances which act as molecular sieves.
The probability of coming into contact with decomposed SF
6
isextremelyremote,anditspresenceinsmallquantities(1-3
ppm) is immediately noticeable because of its sour and un-
pleasantsmell.Ifthishappens,theroommustbeairedbefore
anyone enters it.
The strong infrared absorption of SF
6
and the fact that it re-
mains in the environment for a long time are the reasons for its
highGlobalWarning Potential(GWP),whichis22,200 higher
thanCO2,accordingtotheThirdAssessmentReport.
The GWP (global warming potential) of 1 kg of SF
6
,withrefer-
enceto1kgofCO2,iscalculatedoveratimeperiodof100
years. Its overall contribution to the global greenhouse gas
effect from all applications, amounts to approximately 0.2%.
However,theGWPofSF
6
gas alone is not sufficient for mea-
suring the environmental impact of electric power equipment
based on SF
6
technology.
The environmental impact of any specific application should
be evaluated and/or compared using the Life Cycle Assess-
ment-LCAapproach,asestablishedbyISO14040standards.
The Electric Industry uses SF
6
 in a closed cycle, e.g. in the
circuit-breakersofgasinsulatedsubstations(GIS),inmedium-
voltageandhigh-voltagegasinsulatedcircuit-breakers(GCB),
in igh-voltage gas insulated lines (GIL) and in gas insulated volt-
agetransformers(GVT).InAsia,significantquantitiesofSF
6
are
banked in gas insulated power transformers (GIT) as well.
The Electric Industry is reported to be the most important user
of SF
6
, worldwide. In spite of being the most important user
of SF
6
,theElectricIndustryisalowcontributortotheglobal
emission of SF
6
,farbelowotherindustriesoruserswith“open
applications” of this gas.
However,theimportanceofSF
6
gas as a source of GWP varies
substantiallyfromregiontoregionandfromcountrytocountry,
depending on the proceduresused for handling it, the tight-
ness of the electric power equipment and the amount of gas
banked in electric equipment.
Consultdocument1VCP000264or1VCP000266forinfoabout
the Life Cycle Assessment of apparatus.
Please contact the ABB Assistance Service for information
about how to dispose of SF
6
gas as this operation must only
be carried out by trained and qualified personnel. The persons
to contact are listed at http://www.abb.com/ServiceGuide/al-
phabetical.aspx.
Specific instructions about how to empty the SF
6
gas from the
equipment are available on request (ask for internal document
650551or1VCP000617).
The volume of SF
6
gas in each apparatur is indicated on the
nameplate.