The U.S. Occupational Safety and Health Administration (OSHA) is proposing a definition for “combustible dust” that may be generated in a workplace. The definition would appear in the agency’s Hazard Communication Standard (29 CFR 1910.1200).  The definition would include dust generated in industrial settings such as steel shot blasting and, potentially, some plastic shredding or grinding operations. 

The proposed definition is:    “Combustible dust means finely divided solid particles of a substance or mixture that are liable to catch fire or explode on ignition when dispersed in air or other oxidizing media.“

The current proposal would not mandate control technology, risk analysis, monitoring or retrofits of existing equipment or property.   OSHA is simply proposing to adopt the definition recently issued by the UN Subcommittee of Experts for a Globally Harmonized System (GHS).  If adopted, employers for whom combustible dust is a concern would need to communicate to employees the potential hazard.

The OSHA Hazard Communication Standard (HazCom) has three basic components: 1) container labeling, 2) a written Hazard Communication Plan, and 3) unencumbered access to Safety Data Sheets (SDS).  

RIPA is aware of one reconditioner audited by OSHA several years ago with combustible dust being a prime concern.  In that case, OSHA strongly recommended additional ventilation and that a dust collector be moved outside.

OSHA may choose to take further action in the future.   Currently, regulators look to the Code on Combustible Dust issued by the National Fire Protection Association (NFPA 654).  OSHA inspectors can select particular measures or practices in the NFPA Code and apply them to plants where dust is a concern.

In 2012, OSHA amended the HazCom Standard to “harmonize” its various provisions with those of the UN.  One-time training of employees on these harmonized rules was required by the end of 2014.   RIPA provided training at its 2014 fall Annual Conference.  The training module will be updated to include the official definition of “combustible dust” when it is finalized.   The training module will be useful in educating new employees on GHS-compliant container labels, Safety Data Sheets and the employer’s written Hazard Communication Plan.

RIPA will continue to report on the issue and advise members of measures and practices that can lower the risk of a dangerous event involving potentially hazardous dust.