Implementing a Combustible Dust Program Presented by: Nick Miedema Amway EH&S For: Michigan Safety Conference
Presentation Outline Combustible Dust Overview Current Regulations, Standards and Statistics Amway s Implementation Strategy
Combustible Dust is Everywhere!
Key Terms Combustible Dust: A finely divided combustible particulate solid that presents a flash fire hazard or explosion hazard when suspended in air or the processspecific oxidizing medium over a range of concentrations. (NFPA 654) Combustible Dust: 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 (OSHA NEP)
Key Terms Continued Deflagration Index (K st ): Measure of highest rate of pressure rise (dp/dt) max in bar-m/sec. Understanding the K st of a material is critical for designing explosion protection devices (such as explosion venting and suppression). How quickly will an explosion occur and how severe will be? Class K st (bar-m/s) Common Amway Dusts Impact ST0 0 ST1 1 200 ST2 201 300 ST3 > 300 Pea Protein; Zinc Oxide; Sodium Citrate Cellulose Gum; Cetyl Alcohol; Citric Acid Maltodexrin; Salicylic Acid; Avobenzone Nat. Strawberry Flavor; Nat. Peach Flavor May produce minor structural damage May produce more structural damage May produce substantial structural damage May produce severe structural damage Caution: Do not rely heavily on the Deflagration Index Dust classes are a function of rate of pressure rise, not maximum pressure. Some St-1 dusts have P max on par with St-3 dusts. Understanding K st is critical for design of explosion protection devices.
Key Terms -- Continued Minimum Explosible Concentration (MEC): The minimum concentration of a combustible dust suspended in air, measured in mass per unit volume, which will support a deflagration. The terms LEL [lower explosible limit] or LFL [lower flammable limit] mean the same. Maximum Pressure (P max ): The maximum pressure caused by a dust explosion. Used to design enclosures and predict the severity of the consequence.
Key Terms -- Continued Minimum Ignition Energy (MIE): Measure of sensitivity to ignition by electrostatic discharge. Minimum Ignition Temperature (MIT): Measure of sensitivity to ignition by hot surfaces, friction sparks, and electrical equipment. MIT Cloud: Temperature that a cloud of dust dispersed in the air will ignite at. MIT Surface*: Temperature at which a layer of dust will self-combust (e.g., dust on electrical equipment or other heated surface). * Aka, Minimum Auto-Ignition Temperature (MAIT)
Combustible Dust Incidents and Statistics
Combustible Dust Imperial Sugar Port Wentworth, GA West Pharmaceutical Kinston, NC Hayes Lemmerz Huntington, IN
CSB Investigations and Kst Company Material Involved Kst Deflagration Table Rating AL Solutions Zirconium Dust 75 St-1 CTA Acoustics Phenolic Resin Dust 165 St-1 Hayes Lemmerz Aluminum Dust 131 St-1 Hoeganaes Iron Dust 19 St-1 Imperial Sugar Sugar Dust 35 St-1 West Pharmaceutical Polethylene Dust 140 St-1
1910.178 Powered Industrial Trucks 1910.263, Bakery equipment FM Data Sheet 7-73, Dust Collectors and Collection Systems 1910.261, Pulp, paper, and paperboard mills NFPA 652: Standard on Combustible Dusts (Proposed) 1910.22 Housekeeping CPL 03-00-008 Combustible Dust National Emphasis Program NFPA 654, Standard for the Prevention of Fires and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids 1910.38 Emergency Action Plan 1910.176 Handling Materials-General 1910.157 Portable Fire Extinguisher NFPA 484, Standard for Combustible Metals NFPA 664, Standard for the Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities 1910.272, Grain handling facilities 1910.146 Permit Required Confined Spaces 1910.165 Employee Alarm Systems 1910.94 Ventilation 1910.269, Electric power generation, transmission, and distribution General Duty Clause NFPA 61, Standard for the Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities 1910.307, Hazardous (classified) locations FM Data Sheet 7-76, Prevention and mitigation of Combustible Dust Explosion and Fire 1910.1200, Hazard communication
Fatalities by State 1980 May 2012 1,2 WASHINGTON MONTANA NORTH DAKOTA MINNESOTA MAINE OREGON CALIFORNIA 1 NEVADA 1 2 IDAHO UTAH 1 1 ARIZONA WYOMING COLORADO NEW MEXICO 3 1 SOUTH DAKOTA NEBRASKA TEXAS KANSAS 2 OKLAHOMA 6 3 IOWA 1 MISSOURI WISCONSIN 1 ARKANSAS 2 1 ILLINOIS 8 INDIANA KENTUCKY OHIO MISS ALABAMA GEORGIA 9 5 4 7 MICHIGAN 10 5 9 14 WV 3 NORTH CAROLINA SOUTH CAROLINA NEW YORK PENNSYLVANIA 2 6 VIRGINIA 2 9 1 3 VT NH 4 CONN 6 NEW JERSEY DELAWARE MARYLAND MASS RI No Incidents Deaths Cited by CSB Study 2 LOUISIANA FLORIDA 1 1 Source: Chemical Safety Board Report. Data missing for 2006-2007. 2 Excludes grain handling, coal mining, transportation, and non-manufacturing incidents.
Fabricated Metal Products 7% Rubber & Plastic Products 7% Electric Services 9% Equipment Manufacturing 6% Furniture and Fixtures 4% Food Products 20% Other 10% Amway Incidents Occur in Many Industries Businesses Primary Metal Industries 11% Chemical Manufacturing 11% Lumber & Wood Products 15%
The Science of Combustible Dust Fires & Explosions
Science of Combustible Dust Fires and Explosions Fuel Ignition Oxygen Dispersion / Suspension Confinement
Measures of Explosibility K st, P max Designing explosion protection methods The explosion prevention method of concentration control MEC MIE Identify sources capable of igniting the dust cloud Determine the maximum unprotected surface temperature of process equipment MIT
Flammable or Combustible Dust Characteristics
Aluminum particle size Size (µm) P max (psi) Dp/dt (psi/s) K st (bar-m/s) MIE (mj) 53 123 3,130 59 170 32 133 8,880 167 65 10 9 162 15.370 288 65 4 6 174 15,690 294 75 3 4 167 15,480 291 75 3.5
How Much Dust Must Be Suspended to Support a Flash Fire Rule of Thumb or Explosion? If your arm is fully extended and you cannot see your thumb, there s enough dust to support an explosion and/or flash fire.
The Typical Explosion Event
Amway s Combustible Dust Implementation
What have we done so far? Developed a Facility and Technical Standard Created a Dust Testing Database Conducted Our First Combustible Dust PHA
Facility vs Technical Standard Facility Overview of Classification and Hazard Analysis PPE specific to the facility Equipment Overview Detailed Handling and Housekeeping Procedures Training Requirements Incident Response Technical Gives detailed requirements for the classification and analysis General PPE requirement Detailed requirements for the design of equipment Overview of Housekeeping and Handling
Amway Dust Guidelines Amway allows a dust layer to have a maximum thickness of 1/32. The same thickness of a dime or paperclip.
Combustible Dust Database Safety Data Sheets FM Global Data Outside Testing (Fike, FM & Chilworth) Test for Kst, Pmax, MEC, MIE, MIT GESTIS-DUST-EX: http://www.dguv.de/ifa/gefahrstoffdatenba nken/gestis-staub-ex/index-2.jsp Collected data on almost 200 materials Have over 300 materials total Helps us prioritize our risk analysis Helps to design equipment properly
Is the dust combustible? What preventive and mitigating actions are needed? Is Action Needed? Is dust accumulating or being dispersed? What are combustible dust characteristics?
Process Hazard Analysis
Process Hazard Analyses (PHA) A PHA is the systematic and comprehensive study of a process using recognized methods of hazard analysis to identify, evaluate, and control hazards associated with that process. A PHA is used to help protect both employees and facilities. The goal of the PHA is to identify appropriate controls for combustible dust hazards. A good PHA uses eight steps to address the six questions that should be answered
What-If Analysis This technique uses a brainstorming approach to identify potential safety problems Ask questions along the lines of What if this happens and then seek to answer the question Assesses the significance of the concern, any existing protections, and the need for additional protections Documentation Include each issue considered, the results of the team s evaluation of each issue, and any resulting recommendations.
What-if Steps 1) Divide the system up into smaller, logical subsystems. 2) Identify a list of questions for a subsystem. 3) Select a question. 4) Identify hazards, consequences, severity, likelihood, & recommendations. 5) Repeat steps 2-4 for all subsystems
Process Hazard Analyses (PHA) Cont. Equipment Failures What if a valve leaks? What-if Question Areas Human Error What if the operator fails to restart the pump? External Events What if a very hard freeze persists?
Conclusion Testing data should include Kst, Pmax, MEC, MIE and MIT No regulatory movement since 2010 Important to develop a standard, test your dusts and analyze the hazards
Any Questions? Nick Miedema 616-787-5942 Nick.Miedema@amway.com