A desperate helium shortage is inflating prices on the natural gas faster than a runaway blimp, threatening to burst the dreams — and spike the costs — of everyone from balloon businesses to welders to squeak-voiced party inhalers. “My prices have almost doubled,” said Maureen Curreri Collier, owner of Boston Balloon Events. “A balloon bouquet last year probably off the top of my head would be $15.50 for 11-inch balloons. This year you pay probably $30.” Like natural gas, helium is not renewable. And the federal helium reserves, located in Amarillo, Texas, and managed by the U.S. Department of the Interior, “won’t last 10 years,” said Joe Peterson, assistant field manager for helium resources. “But throughout the U.S. and the world there is enough to last another 50 years.” Peterson said worldwide production has slowed, causing a crunch among refiners. Local companies that depend on helium already are feeling deflated. Christine Bernstein, owner of Balloon City in East Boston, said she’s still able to fill all her orders, but has noticed helium is harder to come by. More... Looks like the future of consumer grade helium is really up in the air.