Monitoring Combustible Dust Minimum Explosive Concentration

Here is a link to an article in this month’s Powder & Bulk Engineering Newsletter on the importance of monitoring combustible dust minimum explosive concentration (MEC) by Jack Osborn, PE of Airdusco Engineering & Design Services, LLC.

Minimum explosive concentration (MEC) is defined in NFPA 652 as the minimum concentration of a combustible dust suspended in air, measured in mass per unit volume (for example, grams per cubic meter), that will support a deflagration, such as an explosion or flash fire.

NFPA 652: Standard on the Fundamentals of Combustible Dust (2016)requires any facility that handles combustible dusts to determine each dust’s explosibility characteristics by testing it. Typically, this involves determining the dust’s K_St, P_max, MEC, and minimum ignition energy (MIE), which is usually measured in millijoules (mJ), but other characteristics may also be important. These determinations are also critical information to have to perform a dust hazards analysis (DHA).