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Sulfur Hexafluoride Safety

Sulfur hexafluoride (SF6) is a gas sometimes used in tracer gas testing. It is odorless, non-flammable, non-toxic and not naturally occurring, which makes it a good candidate for tracer gas tests. However, it does have asphyxiation potential and is a very powerful greenhouse gas, so there are some safety considerations to keep in mind when working with SF6.

  • Much denser than air and can cause asphyxiation if gas displaces air in confined space.
  • Very high greenhouse gas potential – not harmful to people, but harmful to planet. 
  • Hazard Controls:
    • Ventilation – work area should be continually ventilated. 
    • Quantity of gas is limited by only using lecture size cylinders – 0.14 ft3 compressed, 3.4 ft3 expanded.
  • Track usage (amount vented, amount remaining, when and where) for annual greenhouse gas emissions report