The US Chemical Safety and Hazard Investigation Board (CSB) investigated the causes behind chemical incidents. They found that that from 1980 to 2005, there were 281 dust fires and explosions in the USA, killing 119 and injuring 718. In 2008, in a single dust explosion that ripped through an Imperial Sugar Company plant in Port Wentworth, (GA, USA) 13 were killed and 37 injured.
Five main factors occurring simultaneously led to dust explosions: fuel, oxygen, confinement, dispersion, and ignition. Common explosive dusts include aluminum, coal, flour, plastics, powder coatings, resins, rubber, and sugar. Even light accumulations of dust, can create an explosive dust cloud under certain conditions. In the worst explosions, known as "double whammies," external dust is dispersed into the air by explosions in the equipment, which is then ignited by the primary explosion.
The US Chemical Safety and Hazard Investigation Board (CSB), US National Fire Protection Association (NFPA) and US Occupational Safety and Health Administration (OHSA), local fire codes, and voluntary initiatives set standards and provide guidance on preventing dust explosions. However, according to CSB member William E. Wright, published guidelines by these organizations do not "adequately convey combustible dust hazards." He suggests that companies should carefully weigh the risks of not investing in safety.
John M. Cholin, a fire protection-engineering consultant, claims that in cases of dust explosion, companies usually had not complied with the NFPA prevention standards. The CSB, however, does not have the power to shut down plants or to impose fines or penalties when such recommendations are not enforced.
Through investigations, reports, and congressional testimonies, the CSB is hoping to promote awareness among firms to take appropriate measures to prevent chemical accidents. The CSB offers educational and training programs, periodically carries out risk audits, and ensures that facilities have adequate detection and suppression systems to reduce risks. The organization also advises companies to take preventative measures, such as minimizing dust accumulation, reducing oxygen levels in confined collection systems, and eliminating ignition sources.
Related links:
US Chemical Safety and Hazard Investigation Board
US National Fire Protection Association
US Occupational Safety and Health Administration
Video: Take More Action to Prevent Dust Explosions
