1. Combustible Dust National Emphasis Program March 10, 2008 Combustible Dust Oxygen in Air Ignition Source Dispersion Confinement Explosion FIRE Deflagration

4. Malden Mills Methuen, MA December 11, 1995 37 Injured Nylon Fiber Combustible Dust Explosions History

6. Combustible Dust Explosions History Jahn foundry Springfield, MA February 26, 1999 3 dead 9 Injured Phenolic resin dust

7. Ford River Rouge: Secondary Coal Dust Explosion February 1, 1999 Combustible Dust Explosions History Killed six workers and injured 36

8. Combustible Dust Explosions History May 16, 2002 Rouse Polymerics Vicksburg, Ms 5 dead, 7 injured Rubber Dust

10. West Pharmaceutical facility destroyed by polyethylene dust

13. Types of Dust Involved in incidents

14. Types of Industries Involved in Dust Incidents

15. Dust Incidents, Injuries, and Fatalities

22. Particle Size of Common Materials

23. Class II locations are those that are hazardous because of the presence of combustible dust. The following are Class II locations where the combustible dust atmospheres are present: Group E. Atmospheres containing combustible metal dusts, including aluminum, magnesium, and their commercial alloys, and other combustible dusts whose particle size, abrasiveness, and conductivity present similar hazards in the use of electrical equipment. Group F. Atmospheres containing combustible carbonaceous dusts that have more than 8 percent total entrapped volatiles (see ASTM D 3175, Standard Test Method for Volatile Matter in the Analysis Sample of Coal and Coke, for coal and coke dusts) or that have been sensitized by other materials so that they present an explosion hazard. Coal, carbon black, charcoal, and coke dusts are examples of carbonaceous dusts. Group G. Atmospheres containing other combustible dusts, including flour, grain, wood flour, plastic and chemicals . Class II Locations Definitions and Terminology

24. Deflagration Vs. Explosion Deflagration . Propagation of a combustion zone at a speed that is less than the speed of sound in the unreacted medium. Detonation . Propagation of a combustion zone at a velocity that is greater than the speed of sound in the unreacted medium. Explosion . The bursting or rupture of an enclosure or a container due to the development of internal pressure from deflagration. Explosion Deflagration Detonation Definitions and Terminology

26. Source: Dust Explosions in the Process Industries, Second Edition, Rolf K Eckhoff Explosible Range

28. Deflagration Index - Kst Kst = (dP/dt) max V 1/3 (bar m/s) where: (dP/dt) max = the maximum rate of pressure rise (bar/s) V = the volume of the testing chamber (m 3 ) Very strong explosion >300 St 3 Strong explosion >200 and <=300 St 2 Weak explosion >0 and <=200 St 1 No explosion 0 St 0 Characteristic Kst (bar.m/s) Dust explosion class

29. The “Typical” Explosion Event Process Equipment Initial Internal Deflagration Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

30. The “Typical” Explosion Event Time, msec. Process Equipment Initial Internal Deflagration Shock Wave 0 25 50 75 100 125 150 175 200 225 250 300 325

31. The “Typical” Explosion Event Process Equipment Initial Internal Deflagration Elastic Rebound Shock Waves Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

32. The “Typical” Explosion Event Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325 Process Equipment Initial Internal Deflagration Dust clouds caused by Elastic Rebound

33. The “Typical” Explosion Event Process Equipment Containment Failure from Initial Deflagration Dust Clouds Caused by Elastic Rebound Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

34. The “Typical” Explosion Event Process Equipment Secondary Deflagration Initiated Dust Clouds Caused by Elastic Rebound Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

35. The “Typical” Explosion Event Process Equipment Secondary Deflagration Propagates through Interior Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

36. The “Typical” Explosion Event Process Equipment Secondary Deflagration Vents from Structure Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

37. The “Typical” Explosion Event Diagrams Courtesy of John M. Cholin, P.E., FSFPE, J.M. Cholin Consultants, Inc. Secondary Deflagration Causes Collapse and Residual Fires Time, msec. 0 25 50 75 100 125 150 175 200 225 250 300 325

38. Dust Handling Equipment

40. Equipment Involved in Dust Explosions Source: Guidelines for Safe Handling of Powders and Bulk Solids, CCPS, AICHE

61. Laboratory Testing

62. LABORATORY TESTING OF EXPLOSIVE DUSTS

64. Sieve stack

65. Sample Loading

67. Sieved Sample

71. Class II Dust Chamber

72. Dust Loaded

73. Chamber Assembled

75. 20 Liter Chamber

76. Loaded

77. Prepared for Firing