Compiled By Glenn Hasek Armstrong World Industries Inc., a maker of acoustical ceiling tiles, has announced a program that allows building owners to recycle old ceiling tiles rather than dump them in landfills. As part of the program, the Lancaster, Pa.-based company will pay the cost of shipping the tiles to one of its plants. Armstrong will use the old tiles as raw material in the production of new tiles. The company says it is the first recycling program of its kind. Corporations including Microsoft Corp., General Motors Corp., and Aetna Inc. already have participated in the program. All Armstrong ceilings contain recycled materials. While a portion of the content is old scrap ceilings, the company also uses waste products from other industries. Most of that waste is in the form of old newsprint and a byproduct of steel production known as mineral wool. Once a company has a full trailer load of old ceiling tiles, Armstrong will arrange for a truck to pick up the material anywhere in the continental U.S. The company also will pay the freight cost for shipment to one of its nearest plants.