NFPA 31, Standard for the Installation of Oil-Burning Equipment, 2011 edition. NFPA 51B, Standard for Fire Prevention During Welding, Cutting, and Other Hot Work, 2009 edition. NFPA 54, National Fuel Gas Code, 2012 edition. NFPA 68, Standard on Explosion Protection by Deflagration Venting, 2013 edition. NFPA 69, Standard on Explosion Prevention Systems, 2008 edition. NFPA 70®, National Electrical Code®, 2011 edition. NFPA 72®, National Fire Alarm and Signaling Code, 2013 edition. NFPA 85, Boiler and Combustion Systems Hazards Code, 2014 edition. NFPA 86, Standard for Ovens and Furnaces, 2011 edition. NFPA 91, Standard for Exhaust Systems for Air Conveying of Vapors, Gases, Mists, and Noncombustible Particulate Solids, 2015 edition. NFPA 221, Standard for High Challenge Fire Fire Walls, and Fire Barrier Walls, 2012 edition. NFPA 484, Standard for Combustible Metals, 2012 edition. NFPA 505, Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance, and Operations, 2013 edition. NFPA 654, Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids, 2013 edition. NFPA 750, Standard on Water Mist Fire Protection Systems, 2010 edition. NFPA 2001, Standard on Clean Agent Fire Extinguishing Systems, 2012 edition. NFPA 2112, Standard on Garments for Protection of Industrial Personnel Against Flash Fire, 2012 edition. NFPA 2113, Standard on Selection, Care, Use, and Maintenance of Garments for Protection of Industrial Personnel Against Flash Fire, 2012 edition. 2.3 Other Publications. 2.3.1 ASME Publications. American Society of Mechanical Engineers, Three Park Avenue, New York, NY 10016-5990. ASME B31.3, Process Piping, 2012. ASME Boiler and Pressure Vessel Code, 2010. 2.3.2 ASTM Publications. ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West
Soot, pine <10 — 7.9 26 1 [68: Table F.1(b)] Table A.5.2.2(d) 1 m3 Vessel Test Data from Forschungsbericht Staubexposionen – Chemical Dusts Material Mass Median Diameter (μm) Minimum Flammable (g/m3) KSt Dust Hazard Class Adipic acid <10 60 8.0 97 1 Anthraquinone <10 — 10.6 364 3 Ascorbic acid 39 60 9.0 111 1 Calcium acetate 92 500 5.2 9 1 Calcium acetate 85 250 6.5 21 1 Calcium stearate 12 30 9.1 132 1 Carboxy- methyl- cellulose 24 125 9.2 136 1 Dextrin 41 60 8.8 106 1 Lactose 23 60 7.7 81 1 Lead stearate 12 30 9.2 152 1 Methyl-cellulose 75 60 9.5 134 1 Paraformaldehyde 23 60 9.9 178 1 Sodium ascorbate 23 60 8.4 119 1 Sodium stearate 22 30 8.8 123 1 Sulfur 20 30 6.8 151 1 [68: Table F.1(c)] Table A.5.2.2(e) 1 m3 Vessel Test Data from Forschungsbericht Staubexposionen – Metal Dusts Material Mass Median Diameter (μm) Minimum Flammable Concentration (g/m3) (bar) KSt (bar-m/s) Dust Hazard Class Aluminum 29 30 12.4 415 3 Bronze 18 750 4.1 31 1 Iron carbonyl <10 125 6.1 111 1 Magnesium 28 30 17.5 508 3 Phenolic resin 55 — 7.9 269 2 Zinc 10 250 6.7 125 1 Zinc <10 125 7.3 176 1
[68: Table F.1(d)] A.5.2.2(f) 1 m3 Vessel Test Data from Forschungsbericht Staubexposionen – Plastic Dusts Material Mass Median Diameter (μm) (g/m3) KSt Dust Hazard Class (poly) Acrylamide 10 250 5.9 12 1 (poly) Acrylonitrile 25 — 8.5 121 1 (poly) Ethylene (low-pressure process) <10 30 8.0 156 1 Epoxy resin 26 30 7.9 129 1 Melamine resin 18 125 110 1 Melamine, molded (wood flour and mineral filled phenol-formaldehyde) 15 60 7.5 41 1 Melamine, molded (phenol-cellulose) 12 60 127 1 (poly) Methyl acrylate 21 30 9.4 269 2 (poly) Methyl acrylate, emulsion polymer 18 30 202 2 Phenolic <10 15 9.3 129 1 55 7.9 269 2 (poly) Propylene 25 30 8.4 101 1 Terpene-phenol resin 10 15 8.7 143 1 Urea-formaldehyde/ cellulose, molded 13 60 136 1 (poly) Vinyl acetate/ ethylene copolymer 32 30 8.6 119 1 (poly) Vinyl alcohol 26 60 8.9 128 1 (poly) Vinyl butyral 65 30 8.9 147 1 (poly) chloride 107 200 7.6 46 1 (poly) Vinyl chloride/vinyl acetylene emulsion copolymer 35 60 8.2 95 1 (poly) Vinyl chloride/ethylene/vinyl acetylene suspension copolymer 60 60 8.3 98 1 [68: F.1(e)] Table A.5.2.2(g) Explosibility Properties of Metals Material Median (μm) Kst (bar g) Ign Temp (°C) MIE (mJ) MEC UN Category2 LOC1 (v%) Data Source
Manganese < 44 — — 460 305 125 — BuMines RI 6516 16 157 6.3 330 — — — — Eckhoff 33 69 6.6 — — — — — Eckhoff Magnesium 28 508 17.5 — — — — Eckhoff Magnesium 240 12 7 760 500 BZ 5 Eckhoff Magnesium <44 — — 620 40 40 — BuMines RI 6516 Magnesium <44 — 600 240 30 — <3 ( C) BuMines RI 6516 Magnesium ~16 — 7.5 — — 55 — — Cashdollar & Zlochower Molybdenum <10 Not Eckhoff Nickel ~6 Not Cashdollar & Zlochower Niobium 80 238 6.3 560 3 70 6 (Ar) Industry Niobium 70 326 7.1 591 3 50 5 (Ar) Industry Silicon <10 126 10.2 >850 54 125 BZ 3 Eckhoff Silicon, from dust collector 16 100 9.4 800 — 60 — Eckhoff Silicon, from filter <10 116 9.5 >850 250 60 BZ 1 Eckhoff Tantalum <44 — — 630 120 <200 3 (Ar) BuMines RI 6516 Tantalum ~10 ≈3 ≈400 Cashdollar & Zlochower Tantalum 100 149 6.0 460 <3 160 2 (Ar) Industry Tantalum 80 97 3.7 540 <3 160 2(Ar) Industry Tantalum 50 108 5.5 520 <3 160 2(Ar) Industry Tantalum 65 129 5.8 460 <3 160 2(Ar) Industry Tantalum 21 5.6 430 <3 125 Industry
6 0.70 75 174 15,690 294 500 (Pmax), 1,000 (dP/dtmax) 3 5 1.00 70 4 4 0.78 75 167 15,480 291 1,000 (Pmax), 750 (dP/dtmax) 3.5 Spherical Powders 63 0.15 120 101 1,220 23 1,250 (Pmax), 1,000 (dP/dtmax) N.I. Ignition @1 8.0% @ 7.5% 1,750 36 0.25 60 124 4,770 90 1,250 13 30 0.10 60 140 5,940 111 1,000 13 15 0.50 45 148 10,812 203 1,000 7 15 0.30 55 8 6 0.53 75 174 16,324 306 750 6 5 1.30 167 14,310 269 750 Ignition @ 6.0% @ 5.5% 750 5 1.00 70 155 14,730 276 1,250 6 Ignition @ 6.0% @ 5.5% 1,250 3 2.50 95 165 15,900 298 1,250 4 2 3.00 130 For U.S. conversions: 1 m2/g = 4884 ft2/lb; 1 g/m2 = 0.000062 lb/ft2; 1 bar/sec = 14.5 psi/sec; 1 bar·m/sec = 0.226 psi·ft/sec. BET: surface area per unit mass; MEC: minimum explosible concentration; MIE: minimum ignition energy; LOC: limiting oxygen (O2) concentration. Notes:
Where metal or metal-containing dust or powder under the scope of NFPA 484, Standard for Combustible Metal, are present, the requirements of NFPA 484 apply. 8.4.2.7 Steam Blow Down Method. (Reserved) 8.4.3 Training. Operator and contractor training shall include housekeeping procedures, required personal protective equipment during housekeeping, and proper use of equipment. 8.4.4 Equipment. (Reserved) 8.4.5 Vacuum Trucks. 8.4.5.1 Vacuum trucks shall be grounded and bonded. 8.4.5.2 Vacuum truck hoses and couplings shall be static dissipative or conductive and grounded. 8.4.6 Frequency and Goal. 8.4.6.1* Housekeeping frequency and accumulation shall be established to ensure that the accumulated fugitive dust levels on surfaces do not exceed the threshold housekeeping dust accumulation limits. A.8.4.6.1 Surfaces on dust can accumulate can include walls, floors, and horizontal surfaces, such as equipment, ducts, pipes, hoods, ledges, beams, and above suspended ceilings and other concealed surfaces such as the interior of electrical enclosures. Factory Mutual recommends that surfaces should be cleaned frequently enough to prevent hazardous accumulations (FM Data Sheet 7-76, Prevention and Mitigation of Combustible Dust Explosives and Fire, 2.3.5). Housekeeping for fugitive dusts is most important where the operational intent is that the dust accumulations are not normally present in the occupancy and the building has no deflagration protection features, such as damage limiting/explosion venting construction or classified electrical equipment, and additional personal protection from dust deflagration hazards is also not provided. Factors that should be considered in establishing the housekeeping frequency include the following: Variability of fugitive dust emissions Impact of process changes and non-routine activities Variability of accumulations on different surfaces within the room (i.e., floors, overheads) 8.4.6.2 The threshold housekeeping dust accumulation limits shall be in accordance with the industry or
B.3 Overview. B.3.1 A process hazard analysis is a detailed analysis and documentation of the process and the facility housing the process. B.3.2 Each part of the process system is considered for potential deflagration hazard. B.3.2.1 Where the hazard is managed, the means by which it is being managed is documented. B.3.2.2 Where the hazard is not being managed, possible means by which it can be managed should be identified as well as any critical data or parameters that must be quantified before a management method can be applied. B.3.3 Each building compartment, room, or identifiable space should be considered for potential deflagration hazard. B.3.3.1 Where the hazard is managed, the means by which it is being managed is documented. B.3.3.2 Where the hazard is not being managed, possible means by which it can be managed should be identified as well as any critical data or parameters that must be quantified before a management method can be applied. B.3.4 The potential for a dust deflagration should be based upon the potential for all four necessary and sufficient conditions for a deflagration to exist at the point of consideration concurrently. B.3.4.1 The conditions for a deflagration are as follows: (1) A particulate of sufficiently small dimension to propagate a deflagration flame front (2)A means of suspending or dispersing the particulate in air or other oxidizing atmosphere (3) Sufficient quantity of particulate to achieve the minimum explosible concentration (4) Competent source of ignition B.3.4.2 As a general rule in the NFPA standards, there is an assumption that ignition will occur. However, some situations of ignition source control could be determined acceptable by taking into account the consequences (i.e., risk analysis). If a deflagration is possible, the results should be managed in such a way that the objectives of the standard are met. B.3.4.3 The process hazard analysis should classify locations into three general categories: Not a hazard Maybe a hazard Deflagration hazard This will help the owner/operator prioritize management of the hazards. Additionally, it will identify the locations where more information is necessary before a definitive determination can be made. B.3.4.4
D.1.2.4 ASME International Publications. American Society of Mechanical Engineers, Three Park Avenue, New York, NY 10016-5990. ASME Boiler and Pressure Vessel Code, 2010. ASME B.31.3, Process Piping, 2010. D.1.2.5 ASTM Publications. ASTM International, 100 Barr Harbor P.O. Box C700, West Conshohocken, PA 19428-2959. ASTM E 582, Standard Test Method for Minimum Ignition Energy and Quenching Distance in Gaseous Mixtures, 2007. ASTM E 1226, Standard Test Method for Explosibility of Dust Clouds, 2012. ASTM E 1491, Standard Test Method for Minimum Autoignition Temperature of Dust Clouds, 2006 (2012). ASTM E 1515, Standard Test Method for Minimum Explosible Concentration of Combustible Dusts, 2007. ASTM E 2019, Standard Test Method for Minimum Ignition Energy of a Dust Cloud in Air, 2003 (2007). ASTM E 2021, Standard Test Method for Hot-Surface Ignition Temperature of Dust Layers, 2009. ASTM WK1680, Test Method for Limiting Oxygen (Oxidant) Concentration of Combustible Dust Clouds, (draft under development). D.1.2.6 IChemE Publications. Institution of Chemical Engineers, Davis Building, 165-171 Railway Terrace, Rugby, Warwickshire, CV21 3HQ, England. Prevention of Fires and Explosions in Dryers, 1990. D.1.2.7 IEC Publications. International Electrotechnical Commission, 3, rue Varembe, P.O. Box 131, CH-1211 Geneva 20, Switzerland. IEC 61241-2-1, Electrical Apparatus Use in the Presence of Combustible Dust — Methods for Determining the Minimum Ignition Temperatures of Dust, 1994. D.1.2.8 ISO Publications. International Standards Organization, 1 rue de Varembé, Case Postale 56, CH-1211 Genève 20, Switzerland. ISO 6184-1, Explosion Protection Systems — Part 1: Determination of Explosion Indices of Combustible in Air, 1985.
IEC Electrostatics — Part 4-4: Standard Test Methods for Specific Applications — Electrostatic Classification of Flexible Intermediate Bulk Containers (FIBC). 2005. D.1.2.9 U.S. Government Publications. U.S. Government Printing Office, Washington, DC 20402. DOE Handbook, Primer on Spontaneous Heating and Pyrophoricity, DOE-HDBK-1081-1984. OSHA 1910.119, “Process Safety Management of Highly Hazardous Chemicals.” Title 29, Code of Federal Regulations, Part 1910.119, “Process Safety Management of Highly Hazardous Chemicals.” Title 29, Code of Federal Regulations, Part 1910.146, "Permit-Required Confined Spaces." D.1.2.10 Other Publications. Babrauskas, V., Ignition Handbook, Fire Science Publishers, Society of Fire Protection Engineers (SFPE), 2003. Bowes, P.C., Self-Heating: Evaluating and Controlling the Hazards, Elsevier, 1984. Britton, L., Avoiding Static Ignition Hazards in Chemical Operations. New York: CCPS, 1999 Dorsett, G., "Laboratory Equipment and Test Procedures for Evaluating Explosibility of Dusts," Report RI5624. Bureau of Mines, National Institute for Occupational Safety and Health (NIOSH). 1960. Glor, M., Electrostatic Hazards in Powder Handling, Research Studies Press Ltd., 1988. FM Global, "Prevention and Mitigation of Combustible Dust Explosions and Fire," Safety and Health Information Bulletin, Data Sheet 7–76, January 2012. SFPE, Engineering Guide to Fire Risk Assessment, 2006. SFPE, Engineering Guide to Performance-Based Fire Protection Analysis and Design of Buildings, 2000. SFPE, Handbook of Fire Protection Engineering, 2008. Tamanini, F., Dust Explosion Propagation in Simulated Grain Conveyor Galleries, ESV-83-067, National Grain and Feed Association Fire and Explosion Research Report, prepared by Factory Mutual Research Corporation, Norwood, MA, July 2002.