Helium (He)
Helium (He) is colorless, odorless and the lightest of the noble gases.
Helium
Formula: He
CAS No: 7440-59-7
What is Helium Gas?
Helium (He) is a colorless, odorless noble gas. It is the smallest and lightest of the noble gases, so light that it can escape the Earth’s atmosphere. Helium is produced deep underground through the radioactive decay of uranium and its daughter products and is captured by the same geologic formations that trap natural gas. Most helium is produced by extracting it from natural gas.
Industry Applications for Helium
Helium is used in a wide variety of applications due to its unique properties.
Welding
Helium is used in the welding industry as an inert shielding gas for arc welding. It protects the weld area from atmospheric gases like oxygen, nitrogen, and water vapor.
Cryogenics
Taking advantage of its very low boiling point, only a few degrees above absolute zero, helium is used for cryogenic cooling. It is essential for the very cold storage of samples and the cooling of magnets in MRI machines. This can be in open-loop systems where evaporating helium is replaced, or closed-loop helium refrigerators.
Electronics and Lighting
Helium, in mixtures with neon and argon, is used in electronic tubes and neon signs. Its low reactivity and inertness make it ideal for these applications.
Lifting Gas
Helium is lighter than air and nonflammable, making it ideal for use in blimps and balloons. It is used in large balloons for upper atmosphere and cosmic ray studies, and in small balloons by weather forecasters to carry meteorological instruments. Additionally, helium is used in festive balloons.
Aerospace Applications
Helium is used in aerospace applications, including pressure testing and leak testing of propellant tanks. Due to its small atomic size and inertness, helium can slip through gaps that other gases cannot. It is also used to pressurize rocket fuels to force them into rocket engines.
Laboratory Uses
Helium is used in laboratories for leak detection, in dry boxes needing an inert atmosphere, as a temperature standard, and as a carrier gas in gas chromatography. Its inertness and low molecular weight make it ideal for these applications.
Breathing Gas Mixtures
A mixture of helium and oxygen is used as a breathing gas for deep divers who work under high pressures. This mixture, known as heliox, reduces the risk of nitrogen narcosis and oxygen toxicity.
Semiconductor Production
Helium is used in the production of semiconductors. Its inert properties prevent unwanted reactions during the manufacturing process, ensuring the purity and quality of semiconductor materials.
Applications
Specifications
Further Specifications
Cylinder Sizes
- Helium is used in the welding industry as an inert shielding gas for arc welding
- In the cryogenics field
- In mixtures with neon and argon for electronic tubes and neon signs
- Used in large balloons for upper atmosphere and cosmic ray studies and in small balloons by weather forecasters to carry meteorological instruments
- Used in the missile industry to pressurize rocket fuels and force them into rocket engines
- Used in laboratory and research operations as a leak detector, in “dry boxes”, as a temperature standard, as a carrier in gas chromatography, etc.
- Mixture of helium and oxygen is used as a breathing gas for divers who work under high pressures
| Grade 5 | Grade 6 | |
|---|---|---|
| Purity | 99.999% | 99.9999% |
| Nitrogen | < 3 ppmv | < 400 ppbv |
| Oxygen | < 2 ppmv | < 50 ppbv |
| Carbon Dioxide | < 1 ppmv | < 100 ppbv |
| Carbon Monoxide | < 1 ppmv | < 50 ppbv |
| Methane | < 1ppmv | < 100 ppbv |
| Water | < 3 ppmv | < 200 ppbv |
| Chemical & Physical Properties | |
|---|---|
| Molecular Weight | 4.00 |
| Sp. Volume | 97.1 cu.ft/lb |
| Pressure @ 70°F | 2,000 - 2,490 |
| Valve Outlet | CGA 580 DISS 718 |
| Shipping Information | |
|---|---|
| DOT Name | Helium, Compressed |
| Hazard Class | 2.2 |
| DOT No. | UN 1046 |
| DOT Label | Non-Flammable Gas |
| CAS No. | 7440-59-7 |
| Cylinder Size | Fill Volume (cu ft) |
|---|---|
| Tube Trailer | 180,000 |
| 49L/Size 300 | 291 |
*This gas not available for purchase online.
