Airgas, Inc. and subsidiaries (Airgas) is a distributor of industrial, medical and specialty gases (delivered in packaged or cylinder form), and welding, safety and related products (hardgoods). Airgas is a producer of nitrous oxide in the United States, a producer and supplier of dry ice and a supplier of liquid carbon dioxide in the Southeastern United States. The Company is a distributor of process chemicals, refrigerants and ammonia. It has two operating segments: Distribution and All Other Operations. The Distribution segment primarily engages in the distribution of packaged gases and hardgoods. All Other Operations consists of business units that principally produce and distribute carbon dioxide, dry ice, nitrous oxide, specialty gases and anhydrous ammonia, and the joint venture, National Welders Supply Company, Inc. On April 3, 2006, Airgas acquired Byrne Specialty Gases, Inc. On April 4, 2006, it acquired Airtec, Inc. On September 5, 2006, it acquired Aeriform Corporation.