Helium is so cheap and plentiful that it is used to fill Mickey Mouse balloons for children's parties. That's the finding, however obvious, of a report issued in May by the National Research Council on the commercial use of helium. The US government began producing and storing helium under a federal monopoly in the 1920s and later amended the Helium Act to allow commercial producers to enter the market. In 1996, Congress ordered the Bureau of Land Management to stop recovering helium and to sell the reserve. As a precaution it also asked the research council to keep tabs on helium use and pricing. The photonics industry uses helium for HeNe lasers, as a heat transfer agent in fiber optic production and as a shielding gas in laser welding. But those uses take a very minor share of the helium supply. Laser manufacturers use probably less than one-tenth of 1 percent of the world supply of helium, said Curt M. Maier, helium business manager for Air Products and Chemicals Inc. in Lehigh Valley, Pa., a major supplier. Melles Griot Laser Group in Carlsbad, Calif., makes about 100,000 HeNe lasers a year. "Every toy store in America that sells helium balloons uses 100 times more helium than we do, assuming they go through one standard 8-in.-diameter-by-5-ft tank a year, which is what they do," said senior engineer Tom Johnston. "If it's so strategic, then why allow it in the novelty market? That ought to be a clue that it's not strategic," Maier said.