"In the predawn hours of June 21, explosions at the Philadelphia Energy Solutions refinery in South Philadelphia shook houses, sent fireballs into the air and woke up nearby residents.
"Three loud explosions, one after the other, boom, boom boom!" says David Masur, who lives about two miles from the plant and has two young kids. "It's a little nerve-wracking."
Masur watched as the refinery spewed black smoke above the city, easily visible from his home. But what he didn't know at the time was just how close he and his family came to getting exposed to hydrogen fluoride, one of the deadliest chemicals used by refiners and other industrial manufacturers.
Philadelphia Energy Solutions knows that's a possibility. Its worst-case disaster scenario includes 143,262 pounds of hydrogen fluoride released over 10 minutes, which could travel as a toxic cloud for more than 7 miles and impact more than a million people, including in schools, homes, hospitals, prisons, playgrounds, parks and a wildlife sanctuary."
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