Take a deep breath before you enter!!

[WaterbryVTfire]

This stuff is called SF6 gas and is heavier than air....found in high voltage switch gear, medical device testing and used in some breathing apparatus fit testing.



www.fugly.com/videos/6903/invisible_water.html

[MCarpenter]

More information on SF6

here is some more information on SF6.


Super SF6 (Sulfur Hexafluoride) is an inert, non-toxic gas with excellent physical properties, including dielectric, cooling, insulating and arc quenching capabilities. With its unique physical properties, Concorde Super SF6 is ideal for applications such as: electric utilities, magnesium casting, sound insulation, semiconductor etching, nuclear accelerators, scientific and medical instrumentation and more.

SF6 SPECIFICATIONS(Minimum)
Mass Content of Sulfur Hexafluoride (SF6) (%)99.95
Oxygen (O2) 100 ppm vol.
Nitrogen (N2) 250 ppm vol.
Water (H2O) <5 ppm vol.
Hydrolyzable fluoride, expressed as HF 0.3 ppm vol.
Carbon Tetrafluoride (CF4) 100 ppm vol.
Toxicity None

[KenNFD1219]

Here is another video of sulphur hexaflouride. I am using both of these videos in a haz-mat class to demonstrate vapor density.

http://www.youtube.com/watch?v=a9ifZlu6YKk