Office of Safety & Health Consultation presents

1. Office of Safety & Health Consultationpresents Combustible Dust

2. Goal To improve the safety of workers in environments where combustible dusts may be encountered by increasing employee awareness of this hazard and by demonstrating how the hazard can be recognized and addressed in their workplace.

3. Objectives • Identify the elements necessary for dust to explode. • Explain how to prevent dust from reaching combustible levels. • Describe the difference between primary and secondary dust explosions.

4. Introduction • A Chemical Safety Board Study Shows: • From 1996 to 2005, a total of 106 explosions resulted in 16 fatalities and 126 injuries, at an estimated cost of $162.8 million in damages to the facilities. • In 2005, there were 13 grain dust explosions reported in the US.

5. Organic Dust Fires & Explosions • Organic Dust Fires and Explosions: • Massachusetts (3 killed, 9 injured) • North Carolina (6 killed, 38 injured)

6. Massachusetts Incident Fire in a foundry shell molding machine

7. North Carolina Incident • Combustible polyethylene dust accumulated above suspended ceilings at pharmaceutical plant

8. Grain Handling Industry Experience In the late 1970s, grain dust explosions left 59 people dead and 49 injured.

9. Grain Handling Industry Experience In 1987, OSHA promulgated the Grain Handling Facilities standard (29 CFR 1910.272) still in effect

10. Combustible Dust Explosions Malden Mills 2004 Imperial Sugar 2008 Kansas 2011 Dust

11. What’s so bad about a little dust?

12. It’s Only Dust

13. It’s Only Sugar!

14. A Chronology of Past Events • February 7, 2008 – Imperial Sugar Plant explodes • February 11, 2008 – Fire still burning in parts of plant • February 24,2008 – 11th worker dies from injuries • July 2008 – OSHA fines Imperial Sugar Co. $8.8 million For violations in Georgia and Louisiana • August 2008 – 14th worker dies from injuries

15. What’s so bad. • For the employer the millions of dollars in OSHA fines and insurance payments not to mention the cost of rebuilding the plant . • For the workers and their families – the cost, heartbreak and pain – That 14th worker spent 6 months in a burn unit fighting for his life. A total of 40 other workers were injured with severe burns.

16. Between 1980 and 2005 the Chemical Safety Board has knowledge of over 280 dust explosions resulting in 119 deaths and 718 injuries That averages to more than 10 explosions per year Despite the time since the Port Wentworth explosion brought this issue to the national forefront the explosions continue. 10/30/2011 6 killed, 2 injured Kansas

17. Important Points Regarding the CSB Data According to the CSB, “The combustible dust incidents the CSB lists…from 1980 to 2005 are likely only a small sampling, as no federal or state agency keeps specific statistics on combustible dust incidents, nor does any single data source provide a comprehensive collection of these incidents. Information about small combustible dust incidents and near-misses is also generally unavailable. Incidents that cause no fatalities, significant injuries or major fires may not be recorded in the OSHA and fire incident databases The true extent of the problem is likely understated. Due to these limitations, the CSB does not represent the incident data as complete or error free and other compilations of dust explosion data are available.”

18. Dust Incidents, Injuries & Fatalities 1980 - 2005 (Not even close to being a complete summary of incidents) Fatalities Injuries Incidents Injuries / Fatalities Incidents Figure 11. Dust incidents, injuries & fatalities, 1980-2005 Source: Chemical Safety Board

19. Types of Industries Involved in Dust Incidents

20. Types of Dust Involved in incidents

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

22. Combustible Dust Explosions History Jahn Foundry Springfield, MA February 26, 1999 3 dead9 Injured Phenolic resin dust

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

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

25. Combustible Dust Explosions History • January 29, 2003 - West Pharmaceutical Services, Kinston, NC • Six deaths, dozens of injuries • Facility produced rubber stoppers and other products for medical use • Plastic powder accumulated above suspended ceiling ignited

26. West Pharmaceutical facility destroyed by polyethylene dust

27. Combustible Dust Explosions History • February 20, 2003 – CTA Acoustics Corbin, KY • Seven Workers died • Facility produced fiberglass insulation for automotive industry • Resin accumulated in production area and was ignited

28. Combustible Dust Explosions History • October 29, 2003 • Hayes Lemmerz Manufacturing Plant • Two severely burned (one of the victims died) • Accumulated aluminum dust • Facility manufactured cast aluminum automotive wheels

29. Combustible Dust Explosions History • October 30, 2011 • Bartlett Grain Elevator Atchison Kansas - 6 Workers killed - 2 Workers injured Workers were loading corn onto a train

30. Ignition Source The Dust Explosion Pentagon Ignition Source Dispersion Confinement Deflagration Explosion FIRE Oxygen in Air/Oxidizers Combustible Dust To prevent an explosion – remove one corner of the pentagon

31. The primary explosion is rarely the end of the story.

32. Secondary Explosions • Occur when the blast wave from the initial explosion causes accumulated dust in other areas (which may be remote and unrelated to original explosion) to become airborne and explode • Anecdotally many investigators discover that “puffs” (small unreported explosions) had been observed for some time prior to the reported incident.

33. So How Do I Prevent a Dust Explosion? If one of the five elements of the Pentagon is missing a catastrophic explosion cannot occur. = No Explosion

34. Ignition Source Ignition Source Dispersion Confinement Deflagration Explosion FIRE FIRE I Combustible Dust Oxygen in Air/Oxidizers FIRE • Two elements are difficult to eliminate: • Oxygen in Air • Confinement within processes or buildings

35. Ignition Source Ignition Source Dispersion Confinement Deflagration Explosion FIRE Combustible Dust Oxygen in Air/Oxidizers FIRE I But my process doesn’t include dust! Are you sure? If you work with any solid combustible material, ingredients or intermediate products or by-products, handling, conveying, or otherwise manipulating these materials can create combustible dust. Even materials typically handled and stored wet can become dry. FIRE

36. Definitions and Terminology What is Combustible Dust? • NFPA 654 (2006) Definitions • Combustible dust. A combustible particulate solid that presents a fire or deflagration hazard when suspended in air or some other oxidizing medium over a range of concentrations, regardless of particle size or shape. • Combustible Particulate Solid. Any combustible solid material composed of distinct particles or pieces, regardless of size, shape, or chemical composition. • Hybrid Mixture. A mixture of a flammable gas with either a combustible dust or a combustible mist.

37. Definitions and Terminology What is Combustible Dust? • NFPA 69 (2002), and 499 (2004) Definitions • Combustible Dust.Any finely divided solid material 420 microns 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 • 1 micron (µ) = 1.0 x 10-6m  = 1.0 x 10-4 cm = 1.0 x 10-3 mm  •  420 µ = 420 x 10-4 cm = .042 cm = 0.4mm • A typical paper thickness is approximately 0.1mm

38. Different dusts of the same chemical material may have different ignitability and explosibility characteristics depending on variables of particle size, shape, and moisture content. • Good housekeeping might seem like an easy answer.

39. But housekeeping is only part of the answer! • As much as is practical, containment and dust collection systems are important. • But they must be installed and maintained in a manner that keeps them from becoming an ignition source

40. NFPA 654, Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing of Combustible Particulate Solids Recommends: • Minimize the escape of dust from process equipment or ventilation systems: • Use dust collection systems and filters; • Utilize surfaces that minimize dust accumulation and facilitate cleaning; • Provide access to all hidden areas to permit inspection; • Inspect for dust residues in open and hidden areas (at regular intervals); • Clean dust residues (at regular intervals); • Only use vacuum cleaners approved for dust collection; • Locate relief valves away from dust hazard areas; and 9. Develop and implement a hazardous dust inspection, testing, housekeeping, and control program.

41. Use dust collection systems and filters Dust Control • Design of facility & process equipment • Contain combustible dust • Clean fugitive dust • Regular program • Access to hidden areas • Safe cleaning methods • Maintenance

42. Inspect for dust residues in open and hidden areas (at regular intervals); Like most pharmaceutical manufacturers this was a “clean” facility. West Pharmaceutical facility destroyed by polyethylene dust Which accumulated above the tiles in a dropped ceiling

43. NFPA 654, Standard for the Prevention of Fire and Dust Explosions form the Manufacturing, Processing of Combustible Particulate Solids Contains comprehensive guidance on the control of ignition sources: • Use appropriate electrical equipment and wiring methods; • Control static electricity, including bonding of equipment to ground; • Control smoking, open flames, and sparks; • Control mechanical sparks and friction; • Use separator devices to remove foreign materials capable of igniting combustibles from process; • Separate heated surfaces from dusts; • Separate heating systems from dusts; • Proper use and type of industrial trucks; • Proper use of cartridge activated tools; and • Adequately maintain all the above equipment.

44. Ignition Source Control • Electrical equipment • Static electricity control • Mechanical sparks & friction • Open flame control • Design of heating systems & heated surfaces • Use of tools, & vehicles • Maintenance

45. Ignition Source Control • Electrical equipment • Class II, Division 1 and 2 • Class I and Class III may also be an issue • Consider equipment both inside dust handling equipment and outside

46. Ignition Source Control • Mechanical sparks & friction • Rotating equipment bearing failure can lead to very hot surfaces (above the MIT) • Sliding surfaces can develop charges • Steel tools dropping onto concrete or steel • A good mechanical integrity management system/vibration analysis system is needed to detect problems in advance with bearings and other surfaces

47. Ignition Source Control • Mechanical sparks & friction • Open flame control • Use of tools & vehicles • Maintenance • All require effective control of Hot Work • Look for permit systems

48. Ignition Source Control • Design of heating systems & heated surfaces • Know your materials • Minimum Ignition Temperature (MIT) • Maintain temperature controls • Moisture content may be critical

49. Primary Applicable OSHA Standards • 1910.22 General – Housekeeping • 1910.307 Hazardous (Classified) Locations • 1910.178 Powered Industrial Trucks • 1910.263 Bakery Equipment • 1910.265 Sawmills • 1910.272 Grain Handling • General Duty Clause

50. NFPA Standards – Dust Hazards • 61 Agriculture • 68 Deflagration Venting Systems • 69 Explosion Prevention Systems • 70 National Electric Code • 77 Static Electricity • 85 Boiler and CombustionSystems • 86 Ovens and Furnaces • 91 Exhaust Systems