July 24, 2014
The U.S. Chemical Safety Board is renewing its push for a safety standard for combustible dust, which could explode or catch fire. Currently, there is not a combustible dust standard established by the U.S. Occupational Safety and Health Administration. The CSB published a case study of a recycling plant that experienced an explosion that killed or injured several employees. The company involved in the incident processed scrap titanium and zirconium metal. OSHA states various materials, including metal, could be finely divided in a way that makes them prone to fires or explosions.
With the risk of combustible dust causing occupational injuries and fatalities, companies may want to consider ways they can avoid these accidents, such as through good housekeeping practices and maintaining a clean plant floor with.
"Preventable combustible dust explosions continue to occur, causing worker deaths and injuries," CSB Chairperson Rafael Moure-Eraso said in a statement. "The CSB believes it is imperative for OSHA to issue a comprehensive combustible dust standard for general industry with clear control requirements to prevent dust fires and explosions."
CSB Lead Investigator Johnnie Banks said since the metals were being broken down at the facility, this process increased the risk of combustible hazards. The metals were divided into small parts, and size is a factor in combustible dust fires and explosions.
On its website, OSHA said it has started the rulemaking process to make a combustible dust standard for general industry. Last year, the agency also issued guidance for combustible dust hazards, such as when to classify materials as combustible dust, according to Occupational Safety Health Reporter.
"If the material will burn and contains a sufficient concentration of particles 420 microns or smaller to create a fire or deflagration hazard, it should be classified as a combustible dust," the memo said.
How to prevent combustible dust hazards
To determine whether facilities are at risk for combustible dust hazards, companies should implement a hazard analysis and identify which materials could catch fire or explode when they are in a finely divided form, according to OSHA.
In addition to performing a hazard analysis, employers should remind workers about the importance of good housekeeping practices to make sure combustible dust is not covering surfaces and exposed to oxygen, which is a factor in accidents caused by these materials.
As part of their regular maintenance and clean-up operations, companies that often have metal shavings or parts on plant floors may want to invest in magnetic sweepers to prevent any build-up of metallic materials that could potentially catch fire or explode in the right conditions.