Implementing a Combustible Dust Program. Presented by: Nick Miedema Amway EH&S For: Michigan Safety Conference

Transcription

1 Implementing a Combustible Dust Program Presented by: Nick Miedema Amway EH&S For: Michigan Safety Conference

2 Presentation Outline Combustible Dust Overview Current Regulations, Standards and Statistics Amway s Implementation Strategy

3 Combustible Dust is Everywhere!

4 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)

5 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 ST ST 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.

6 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.

7 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)

8 Combustible Dust Incidents and Statistics

9 Combustible Dust Imperial Sugar Port Wentworth, GA West Pharmaceutical Kinston, NC Hayes Lemmerz Huntington, IN

10 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

11 Powered Industrial Trucks , Bakery equipment FM Data Sheet 7-73, Dust Collectors and Collection Systems , Pulp, paper, and paperboard mills NFPA 652: Standard on Combustible Dusts (Proposed) Housekeeping CPL 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 Emergency Action Plan Handling Materials-General 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 , Grain handling facilities Permit Required Confined Spaces Employee Alarm Systems Ventilation , 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 , Hazardous (classified) locations FM Data Sheet 7-76, Prevention and mitigation of Combustible Dust Explosion and Fire , Hazard communication

12 Fatalities by State 1980 May ,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 MICHIGAN WV 3 NORTH CAROLINA SOUTH CAROLINA NEW YORK PENNSYLVANIA 2 6 VIRGINIA 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 Excludes grain handling, coal mining, transportation, and non-manufacturing incidents.

13 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%

14 The Science of Combustible Dust Fires & Explosions

15 Science of Combustible Dust Fires and Explosions Fuel Ignition Oxygen Dispersion / Suspension Confinement

16 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

17 Flammable or Combustible Dust Characteristics

18 Aluminum particle size Size (µm) P max (psi) Dp/dt (psi/s) K st (bar-m/s) MIE (mj) , , , ,

19 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.

20 The Typical Explosion Event

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22 Amway s Combustible Dust Implementation

23 What have we done so far? Developed a Facility and Technical Standard Created a Dust Testing Database Conducted Our First Combustible Dust PHA

24 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

25 Amway Dust Guidelines Amway allows a dust layer to have a maximum thickness of 1/32. The same thickness of a dime or paperclip.

26 Combustible Dust Database Safety Data Sheets FM Global Data Outside Testing (Fike, FM & Chilworth) Test for Kst, Pmax, MEC, MIE, MIT GESTIS-DUST-EX: 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

27 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?

28 Process Hazard Analysis

29 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

30 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.

31 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

32 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?

33 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

34 Any Questions? Nick Miedema