12 injured when duct falls at Pa. school PITTSBURGH, April 4 (UPI) -- An air duct crashed onto a lunch table in the cafeteria at a Pittsburgh-area elementary school, trapping several children underneath. Eight students and four adults were hurt Tuesday at Shaler Area Elementary School, the Pittsburgh Post-Gazette reported. Seven children were taken to Children's Hospital of Pittsburgh, where three were in good condition, three in fair condition and one had been released by Tuesday evening. The large section of air vent pipe came crashing down at 11:30 a.m., while fourth-graders were eating lunch. "We were just sitting there and then we heard a big boom and then pipe fell on one of the lunch tables," Haley Monahan, a fourth-grader, told the newspaper, adding that water "started exploding." Engineers joined local police in investigating the crash, the Pittsburgh Tribune said. Two of the injured adults were taken to a hospital. Two adults and a child were treated by paramedics at the scene.