Combustible Dust: A Preventable Hazard

In many instances combustible dust goes unrecognized which may lead to the possibility of tragic consequences. Many industries are presented with the hazards of combustible dust such as: chemical, food, fertilizer, pulp, pharmaceutical, plastic, tire and rubber manufacturers, recycling, and textile. It is important for the safety of the employees and any visitors to a facility that the possibility of a combustible dust explosion be addressed.

   Combustible dust is defined by the National Fire Protection Association (NFPA) 654 as "any finely divided solid material that is 420 microns or smaller in diameter (material passing a U.S. No 40 Standard Sieve) and presents a fire or explosion hazard when dispersed and ignited in air." When a dust explosion occurs the combustible dust is suspended in air in a contained space with an oxidant (in most cases oxygen) and is presented with an ignition source. Common ignition sources are open flames, sparks, friction, static electricity, hot surfaces, and electrical wiring.

   To prevent combustible dust explosions OSHA recommends a thorough hazard assessment to help identify contributing factors. This assessment should include looking at the materials being handled, procedures used in the operation, any space that the material may enter, and ignition sources. When trying to control the dust it is important to have a program designed for routine inspections, testing, and cleaning procedures. It is best to perform routine inspections of all areas the combustible dust may enter. When cleaning it is important to pay close attention to ignition sources and use only vacuum cleaners approved for combustible dust collection. Don't wait until it's too late to address this issue.

   To learn more about Combustible dust contact Carolina Filters, Inc. or visit www.osha.gov or www.nfpa.org to review the National Fire Protection Association (NFPA) standards.

November 2010