Hydrogen is the lightest gas known. It is a colorless, odorless and tasteless gas and is flammable and nontoxic at atmospheric temperatures and pressures.
The Compressed Gas Association (CGA) specification G-5.3 is the industry standard. Type II, Grade A is considered commercial liquid hydrogen and Type I, Grade B is considered commercial gaseous hydrogen.
Hydrogen
(Units in ppm (v/v) unless show otherwise)

* For vaporized liquid, the typical analyses are Hydrogen, 99.995%; O2/Ar, 1.0 ppm; N2/Total Hydrocarbons, 9.0 ppm; CO2/CO, 1.0 ppm.
** Includes water
Keen guarantees commercial grade product delivered as a liquid meets the commercial CGA specification listed. Keen does not normally guarantee commercial grade product delivered as a compressed gas meets the gaseous specification listed because gas purities are affected by normal cylinder filling practices and process procedures which may compromise the integrity of the product.

Hydrogen Conversion Data
|
Hydrogen
|
Weight
|
Gas
|
Liquid
|
|
Pounds
|
Kilograms
|
Cubic Feet
|
Cubic Meters
|
Gallons
|
Liters
|
|
Lb
|
Kg
|
SCF
|
Nm3
|
Gal
|
L
|
|
1 Pound |
1
|
0.4536
|
192
|
5.047
|
1.6928
|
6.408
|
|
1 Kilogram |
2.205
|
1
|
423.3
|
11.126
|
3.733
|
14.128
|
|
1 SCF Gas |
0.005209
|
0.002363
|
1
|
0.02628
|
0.00882
|
0.03339
|
|
1 Nm3 Gas |
0.19815
|
0.08988
|
38.04
|
1
|
0.3355
|
1.2699
|
|
1 Gal Liquid |
0.05906
|
0.2679
|
113.41
|
2.981
|
1
|
3.785
|
|
1 L Liquid |
0.15604
|
0.07078
|
29.99
|
0.7881
|
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.