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Former Chemical Safety Board Chairwoman points finger at OSHA

Feb. 9, 2008
Dixie Crystals Blast AftermathThe fingerpointing and blame assigning is already starting, even though we don't yet know what really caused the explosion, deaths and injuries at the Imperial Sugar Dixie Crystals plant near Savannah, Ga., Thursday night. Accordi...
The fingerpointing and blame assigning is already starting, even though we don't yet know what really caused the explosion, deaths and injuries at the Imperial Sugar Dixie Crystals plant near Savannah, Ga., Thursday night. According to an Associated Press story, over 300 explosions over the past 28 years have killed more than 120 workers-- and all of them have been linked to dust explosions in silos. Take a minute and realize that one of the most potent weapons in the US Air Force arsenal for air support is a type of bomb made with what is known as Fuel-Air-Explosives. FAE weapons use a fine cloud of hydrocarbon fuel, mixed with (usually) aluminum dust, and an ignition source. This is exactly the same kind of explosion that happens when a cloud of, for example, sugar dust, or for another example, grain dust, is exposed to an ignition source in a silo. Boom! "This is an extremely dangerous component that is not regulated," former safety board chairwoman Carolyn Merritt told The Associated Press Friday. Dust explosion situations "are so dangerous that people have got to pay attention to this. There should be an outcry." I have to agree. There should be an outcry. Safety experts agree that this problem is relatively easy to prevent. All the prevention designs revolve around removing the fine dust as it forms, and not allowing it to form clouds over the coarser material in the silo. Removal of this dust, however, normally means that the entire silo needs to be pressurized, which is expensive, and absolute prevention requires a nitrogen blanket on top of the material, instead of an air space containing oxygen. Both of these are very expensive, and there has been sufficient resistance from the industries involved that OSHA has hesitated for over 25 years to make tough regulations, and then enforce them. The AP report continues: "But that has not been required by the Occupational Safety and Health Administration, which is part of the Labor Department. The U.S. Chemical Safety Board, which investigates industrial accidents, concluded in a report in 2006 that OSHA had no comprehensive regulation to prevent dust explosions and that its program "inadequately addresses" the problem. "A 20-year-old OSHA dust regulation aimed only at grain plants and silos is effective, the safety board said, and shows why regulations are needed for other companies." According to OSHA, they began stepping up enforcement last October...but obviously that was too little, and too late for the people at the Dixie Crystals plant. It's time for the industries that use silos that can have FAE explosions to step up and do it themselves. It is time for them to clean up their own acts, for once. Who are they? Why the food, agribusiness, plastics and chemicals industries. The same ones who generally subscribe to the SIS requirements in ANSI/ISA84 and the IEC 61511 standards. Come on, let's stop killing people when we don't have to. It isn't possible to prevent all accidents, but there are unexpected accidents, and there are accidents-waiting-to-happen. It is the latter type we CAN and we MUST prevent.