Industrial gases are inextricably woven into the fabric of modern manufacturing. From the primary extraction of raw materials, through their intermediate processing to manufacture metals, chemicals and ceramics, to the fabrication of sophisticated industrial, consumer and food products, gases are used across the whole spectrum of industry. The isolation, manufature and supply of these gases is a major industry in itself; the 300 million tones of gas used each year generates sales in excess of $20 billion. In terms of tonnage, nitrogen has become the most used industrial gas, finding...