Helium

(Liberty Industrial Gases supplies a full range of industrial gases in a variety of cylinder sizes for all your gas needs. the capability of providing pure gases along with customized mixing of component gases to meet all your welding needs.)

Properties of Helium

Helium is a tasteless, odorless, nonflammable, non-toxic, inert gas. The smallest of all molecules, helium is the second lightest elemental gas, after hydrogen.

Helium is produced continually by the radioactive decay of uranium and other elements, gradually working its way into the atmosphere. However, commercial extraction from air is impractical because helium’s concentration is only about five parts per billion.

Most of the world’s helium comes from the Texas panhandle, Oklahoma, Kansas and the Rocky Mountains’ eastern flank, other sources include the Middle East and Russia. Praxair produces helium at its facilities in Bushton and Ulysses, KS and offers a worldwide distribution capability

Helium is a colorless, odorless and tasteless inert gas which has no toxic properties. A member of the rare gas chemical family, it is 1/7 as heavy as air. Liquid Helium at -452ºF is the coldest liquefied gas.

The Compressed Gas Association (CGA) specification G-9.1-1992, Type I, Grade D is considered the commercial gaseous helium standard.

(Units in ppm (v/v) unless show otherwise)

Limiting Characteristics CGA G-9.1

Type I, Grade D

Typical
Helium Minimum, % 99.5 99.7
Maximum Guaranteed Impurities 50
Water 15 15
Dew Point, °F
Oxygen 5 5
Nitrogen

Type II liquid helium, when passed through a 10 micron absolute filter at less than 5.2ºK is pure helium for which no analysis is necessary.

The water content of helium required for any particular grade and application may vary with intended use. If a specific limit is required, it should be specified as a limiting concentration expressed in ppm (v/v) or the dew point equivalent. Also note that the water content of grades 4.5 and higher will be about 10 ppm higher when supplied in Pyrex glass flasks.

The Quality Verification Levels apply only to gaseous helium. Impurity limits for liquid helium are not specified since sufficient technical data and analytical procedures are not available to warrant a definitive quantitative specification. The requirement for insuring that the loaded fluid in a container is liquid helium can be satisfied by analyzing the shipping container vent gas or by demonstrating that the temperature of the loaded fluid is below the hydrogen triple point 13.88K).

Helium Conversion Data

Helium Weight Gas Liquid
Pounds Kilograms Cubic Feet Cubic Meters Gallons Liters
LB KG SCF Sm3 Gal L
1 Pound

1

0.4536

96.71

2.736

0.9593

3.631

1 Kilogram

2.205

1

213.2

6.039

2.115

8.006

1 SCF Gas

0.0103

0.00469

1

0.02832

0.009919

0.03754

1 Sm3 Gas

0.3651

0.1656

35.31

1

0.3504

1.3257

1 Gal Liquid

1.0423

0.4728

100.8

2.854

1

3.785

1 L Liquid

0.2754

0.1249

26.63

0.7542

0.2642

1

SCF (standard cubic foot) and SM3 (standard cubic meter) gas measured at 1 atmosphere and 70ºF.
Liquid measured at 0ºF and saturated pressure.
Nm3 (normal cubic meter) gas measured at 1 atmosphere and 0ºC.
All values round to the nearest 4/5 significant numbers.