How does sulfur hexafluoride get into the atmosphere?

The most important means by which SF6 gets into the atmosphere is from leaks in the electricity industry. Electrical company Eaton, which manufactures switchgear without SF6, says its research indicates that for the full life-cycle of the product, leaks could be as high as 15\% – much higher than many other estimates.

How is sulfur hexafluoride used?

Sulfur hexafluoride is used chiefly as an insulating medium for a wide range of high voltage electrical and electronic equipment. Sulfur hexafluoride (SF6) /is/ used as an electrical insulating material in circuit breakers, cables, capacitors, and transformers .

How long does SF6 stay in the atmosphere?

Sulfur hexafluoride is inert in the troposphere and stratosphere and is extremely long-lived, with an estimated atmospheric lifetime of 800–3,200 years.

How much sulfur hexafluoride is in the atmosphere?

The amount of the gas – known as SF6 – in the atmosphere is minute, only about three parts per trillion by volume, but its global warming potential is significant.

Why is sulfur hexafluoride useful in electrical switches?

SF6 gas is extremely chemically stable, non-flammable and highly electronegative, with an excellent dielectric property of approximately 2.5 times more than air. Therefore, it is commonly used in electrical switchgear, transformers and substations as an electrical insulation, arc quenching and cooling medium.

What emits sulfur hexafluoride?

There are no natural sources of sulfur hexafluoride; it originates entirely from human activities. It has a very long atmospheric lifetime.

Why Sulphur hexafluoride is used as a gaseous electrical insulator?

SF6 is a colourless, odourless and non-toxic gas at room temperature. It is thermally stable and chemically inert. Because of its inertness and high tendency to suppress internal discharges, it is used as a gaseous electrical insulator in high voltage generators and switch gears.

How is sulfur hexafluoride released?

Atmospheric emissions occur during equipment maintenance or leaks. In addition to electrical equipment, SF6 may be intentionally released directly to the air in small amounts as a tracer compound for air dispersion studies.

How does sulfur hexafluoride affect the environment?

It is a potent greenhouse gas with a high global warming potential, and its concentration in the earth atmosphere is rapidly increasing. During its working cycle, SF6 decomposes under electrical stress, forming toxic byproducts that are a health threat for working personnel in the event of exposure.

How is sulfur hexafluoride produced?

It was first reported in 1900 by Henri Moissan (picture, left), the discoverer of fluorine. It is usually made by burning sulphur in an atmosphere of fluorine, though it can be prepared by pyrolysis of SF5Cl (whose synthesis does not require the use of elemental fluorine).