Combustible Dust

A dry downdraft table pulls dust and fume through dry filter media, while a wet downdraft table (like our Storm series) draws air through a water bath, which captures sparks and combustible dust before they reach a filter. Wet tables are generally the safer choice for processes that generate hot sparks, aluminum or magnesium dust, or other combustible fines where a dry filter would pose an ignition risk.

Requirements vary by state and local jurisdiction, but combustible dust applications are generally subject to NFPA 61, 654, 68, and 69, and OSHA's general duty clause even where a specific combustible-dust standard hasn't been formally adopted. Our System Audits & Testing service can help document that a new or existing system meets applicable standards; see our Safety section for a plain-English overview.

A spark detection and extinguishing system (like our Raptor line) continuously monitors ductwork for sparks or embers generated upstream by grinding, cutting, or other hot processes, and automatically extinguishes them with a water mist before they reach a filter or collector where they could ignite accumulated dust. It's typically recommended wherever a process both generates sparks and feeds a dry dust collection system.

An explosion vent (like our Vigilex domed or flameless vent panels) is designed to relieve pressure safely to the outside of a vessel if a dust explosion occurs inside it. An explosion isolation valve (like our Vigiflap valves) is designed to stop flame and pressure from traveling through ductwork from one piece of equipment to another, preventing a secondary explosion elsewhere in the system. Most combustible-dust systems use both as part of a layered protection strategy.