• Helium is a rare gas which is extremely light, colourless, odourless, inert, non-toxic and non-flammable. It is also an “ecological” gas with no impact on the environment or the ozone layer.

  • Helium exists abundantly in the sun atmosphere, representing approx. 30% of all present gases around the sun. But only traces of helium can be found in the earth atmosphere. However, it can also be found in fossil form in natural gas pockets of some oil fields (mainly in the USA, Algeria, Qatar, Russia).

  • The gaseous by-product obtained during the liquefaction of natural gas, rich in helium, is used as feed gas for the helium extraction plant. Depending on the liquefaction process used, the helium content of this feed gas varies between 4 and 15%.

Applications of helium

  • The field of application of helium is very wide. It is not only used to inflate party balloons! Its unique physical, chemical and biological properties makes gaseous helium useful in most of “high tech” applications such as:
    • Spatial industry (Ariane 5), aeronautics, car industry (airbags), research (chromatography), leakage detection, telecommunication (quenching of optic  fibers), diving (mixed with oxygen, it is used for deep-diving), meteorology (atmospheric probes) and in particular welding gas mixtures.

  • In its liquid state, helium is the coldest of all fluids
    and its temperature of -268,9°C is very close to the
    absolute zero (-273.15°C). This property is used for manufacturing supra-conductive magnets, medical
    imaging (IRM) as well as for the fundamental research :
    particle accelerators, prototypes of nuclear fusion reactor, plasma physics, etc…

Physical Properties of Helium
Metric Units US Units
Symbol He He
Atomic Mass 4.00 4.00
Boiling Temperature
(at 1013 mbar)
- 268,9 °C - 452.06 °F
Liquid Density
(at boiling point)
125 kg / m3 9'728 lb / cu ft
Vapour Density
(at boiling point)
16,8 kg / m3 1'315 lb / cu ft
Liquid Heat Capacity
(at boiling point)
4,54 kJ / Kg / °C 1,083 Btu / lb / °F
Vapour Heat Capacity
(at boiling point)
5.19 kJ / Kg / °C 1,2381 Btu / lb / °F
Vaporisation Heat
(at boiling point)
20,28 kJ / kg 8,72 Btu / lb

Conversion table for helium
Weight Gaseous Liquid
Pound (lb) kilogramme (kg) Std Cubic Foot (scft) Normal Cubic Meter (Nm3) gallon (gal) Liter (l)
Pound (lb) 1 0,4536 96,71 2,541 0,9593 3,631
kilogramme (kg) 2,205 1 213,21 5,600 2,115 8,006
Cubic Foot (scft) 0,01034 0,00469 1 0,02627 0,009919 0,03754
Nm3 (gaseous) 0,3936 0,17856 38,05 1 0,3775 1,4289
Gallon (liquide) 1,042 0,4728 100,8 2,649 1 3,785
Liter (liquide) 0,2754 0,1249 26,63 0,6998 0,2998 1
Normal Cubic Meter (Nm3) refers to 0°C et 1013 mbar
Standard Cubic Foot (scft) refers to 21°C (70 °F) et 1013 mbar
"Liquid" refers to the boiling point (4,2 K and 1013 mbar)
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