(see also “Powder”). Any finely divided solid material, 425 mm or less in diameter (i.e., material passing through a U.S. No. 40 standard sieve), that presents a fire or explosion hazard when dispersed and ignited in air or other gaseous oxidizer.
NOTE: Online conference registration, membership renewal, and other online transactions will be unavailable between 3 AM EDT and 9 AM EDT. We apologize for the inconvenience.