(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 Oxygen

Oxygen, or O2, which comprises 21 percent of the earth’s atmosphere, supports life and makes combustion possible. The most abundant of all elements on earth, oxygen comprises 85 percent of its oceans and, as a component of most rocks and minerals, 46 percent of its solid crust. In addition, it constitutes 60 percent of the human body.

Colorless, odorless and tasteless, oxygen has poor solubility in water. A specific gravity of 1.105 makes it slightly heavier than air. When cooled to its boiling point of -297°F (-183°C), oxygen becomes a transparent, pale blue liquid that is slightly heavier than water.

Oxygen reacts with all elements, except inert gases, to form compounds called oxides. The rate of reaction – known as oxidation – varies. For example, magnesium oxidizes very rapidly, igniting spontaneously in air. However, noble metals, such as gold and platinum, oxidize only at very high temperatures.

Although oxygen itself is nonflammable, it enhances combustion and enables all materials that are flammable in air to burn much more vigorously. These combustion-supporting properties account for its use in many industrial applications.

Oxygen is the most abundant element on the earth’s surface and as a gas is indispensable in respiration. Composing almost 21% of the atmosphere, oxygen is a colorless, odorless and tasteless gas which supports combustion. As a liquid at -297ºF, oxygen is light blue in color and is approximately 14% heavier than water.

Liquid oxygen is classified as a Type II by the Compressed Gas Association (CGA). CGA Pamphlet G-4.3, Type II, Grade B and the United States Pharmacopia (USP) specs are considered standards for commercial liquid oxygen.

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

    Liquid Liquid Gasseous
Limiting Characteristics USP CGA G-4.3
Type II, Grade B
Typical CGA G-4.3
Type I, Grade B
Oxygen Minimum, % 99.0 99.5 99.7 99.5
Water N/A 6.6 1 None condensed
Dew Point, °F N/A -82 -105  
Total Hydrocarbons as Methane N/A N/A 30  

Oxygen is also available in high purity VLSI grade and ultra high purity ELSI grade (99.9999) liquid oxygen for customer requiring stringent purity standards.

Oxygen Conversion Data

Oxygen Weight Gas Liquid
Pounds Kilograms Cubic Feet Cubic Meters Gallons Liters
1 Pound 1 0.4536 12.078 0.3173 0.105 0.3975
1 Kilogram 2.205 1 26.632 0.6996 0.2315 0.8762
1 Ton 2000 907.2 19342 508.6 172 651
1 SCF Gas 0.1034 0.0469 1 0.02628 0.008893 0.03366
1 Nm3 Gas 3.933 1.784 38.04 1 0.3382 1.2802
1 Gal Liquid 11.63 5.276 112.5 2.957 1 3.785
1 L Liquid 3.072 1.3936 29.71 0.7812 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.