To help answer this question, NFPA has released NFPA-652 and 654. A combustible dust is defined as a finely divided combustible particulate solid that presents a flash fire or explosion hazard when suspended in air or the process-specific oxidizing medium over a range of concentrations. Basically, what this means is when the dust is in the air and its concentration is enough to cause a flash fire or propagate a deflagration or explosion if exposed to a spark or heat source, then it’s considered combustible.
Posts about Particulate in Dust Collection System (2):
4 Potential Dangers to Collectors! How Cyclone Pre-Filters Can Help!
With government regulations tightening on solid emissions, baghouses and cartridge collectors have become status quo in the past 40 years. The fabric filters (bags or cartridges) remove dust below 1 micron in size. The high removal efficiency of the filters, have been considered best available removal technology. This means most processes requiring dust collectors will use a baghouse or cartridge collector. However, not all processes work well with baghouses and dust collectors.