On the evening of February 7, 2008, the Imperial Sugar refinery at Port Wentworth, Georgia — a sprawling plant on the Savannah River that refined about nine percent of the nation’s sugar — was running as normal when, at about 7:15 p.m., a dust explosion tore through the enclosed steel belt conveyor that ran beneath its great storage silos.
Sugar dust had built up inside the conveyor, which had recently been enclosed with steel panels that allowed an explosive concentration to gather; an overheated bearing most likely set it off. The first explosion blew outward into the packing buildings, where spilled sugar and dust lay deep on floors and high surfaces throughout. It threw that dust into the air and touched off a rolling series of secondary explosions and fires across the plant. Fourteen workers were killed — eight at the scene and six who later died of their injuries in hospital — and 36 more were seriously injured, many of them badly burned.
The U.S. Chemical Safety Board, reporting in September 2009, called the disaster “entirely preventable”. The sugar industry had known of the dust explosion hazard since the 1920s, yet the plant’s conveying equipment was neither designed nor maintained to keep dust from escaping, housekeeping let combustible sugar accumulate throughout the buildings, and airborne dust inside the enclosed conveyor had risen above the minimum explosible concentration. The Board pointed, too, to the gap at the centre of the case: it had recommended in 2006, after a study counting 281 combustible dust explosions in the United States since 1980, that OSHA issue a comprehensive dust standard — and by 2008 none existed.
OSHA proposed fines of some $8.7 million against Imperial Sugar for hundreds of violations at its Georgia and Louisiana plants. In 2010 the company settled the citations for just over $6 million and agreed to a programme of safety improvements at both refineries; the Department of Justice ultimately brought no criminal charges over the explosion.
The disaster pushed combustible dust to the front of American industrial safety. The House of Representatives passed a bill in 2008 that would have ordered OSHA to issue an interim dust standard; it did not become law, and the Chemical Safety Board continued to press for a comprehensive standard as its central unfinished recommendation. The Port Wentworth refinery was rebuilt and returned to production.
Download the CSB Investigation Report (3 MB file)