OSHA’s Top 10 Indicators that a combustible dust hazard may be present

Ever wonder what an OSHA Compliance Safety and Health Officer (CSHO) looks for to establish that a combustible dust hazard may be present?  Here are the top 10 indicators they look for when wondering if the business has a Combustible Dust…

1. Significant visual accumulations of known combustible dusts found on elevated surfaces (due to poor housekeeping practices).
2. Indoor dust collection systems (such as media dust collectors or cyclones) handling dust known to be combustible and without any recognized means of explosion protection (such as deflagration venting to a safe outdoor location, deflagration venting through a listed dust retention and flame arresting device, or deflagration detection and chemical suppression).
   1. Outdoor dust collection systems handling dust known to be combustible and without any recognized means of explosion protection, and which may result in exposure to employees working outdoors, taking breaks outdoors, or in the path of an exit door/route.
   2. Dust collection systems handling dust known to be combustible and without any recognized means of deflagration propagation protection (isolation) to protect upstream work areas or equipment and other vessel openings, such as any material hopper discharge openings or exhaust air ducting (if exhausting indoors).
3. Dust collection systems handling dust known to be combustible and which are noted to be either directly exhausting air indoors (indoor collector) or returning exhausted air back indoors (outdoor collector).
4. Other equipment (e.g., bucket elevators, size reduction equipment, ovens, dryers, or storage vessels) processing, transporting, storing, or handling dust known to be combustible and which are installed, equipped, maintained, or operated in a manner contrary to the manufacturer and/or industry standards.
5. Evidence of improper operation or maintenance of dust-generating equipment which could result in deflagration or explosion damage to the equipment and/or area.
6. Evidence of combustible dust-related fire, deflagration, or explosion damage within the facility, or on or within the process, transport, storage, or collection equipment.
7. The visible dust cloud, or clouds, of dust known to be combustible (such as through leaks in equipment, or transfer points).
8. Visible fire damage evident on equipment or building walls.
9. Historical information such as incident reports, or frequent or recent fire department responses, that address combustible dust fire, deflagration, or explosion events for which no corrective measures have been put in place.
10. Any other information the CSHO is able to document which indicates the likely existence of a combustible dust fire, deflagration, or explosion hazard that is not being adequately controlled by the employer.

 Source:  https://www.osha.gov/sites/default/files/otm_secIV_chap6.pdf