| Helium is a non-flammable, colorless, odorless gas which is the
second lightest element know. Its concentration in the atmosphere
of just 0.0005% also makes it one of the most rare gases.
Natural gas wells store helium and provide the principle
source of this gas, which is extracted by a stripping process.
After hydrogen, helium has the smallest molecular
cross-section of any gas. Its permeation rate and ease of
detectability make it an ideal medium for leak detection.
Helium is widely used as a shielding gas for arc welding and
as an inter gas in the production of reactive materials, and safely fill
the need to replace hydrogen in lighter-than-air applications. Helium
is also used for balloon filling. |
