OSHA has been piece-mealing its own standards along with NFPA standards to formulate a Combustible Dusts National Emphasis Program (NEP) since the 2008 Port Wentworth, GeorgiaSugar Refinery explosion. There is always some confusion about OSHA using consensus standards outside of their own safety standards and when it comes to Com Dust enforcement, they rely heavily on the NFPA standards. Here we discuss which of those NFPA standards apply and OSHA also tells us when those NFPA standards would NOT apply.
And of course, OSHA will also use the FREE FM Global Data Sheets as well!
NFPA Fundamental Industry Standards
NFPA 652, Standard on the Fundamentals of Combustible Dust
CSHOs should review NFPA 652 before looking into other combustible dust standards and recommended practices. This standard provides the basic principles for identifying and managing fire and explosion hazards of combustible dusts and particulate solids. It also has provisions to manage fire, flash fire, and explosion hazards caused by combustible dusts. It further directs the user to other industry- and commodity-specific NFPA standards with relevant provisions.
NFPA 652 applies to facilities and operations that manufacture, process, blend, convey, repackage, generate, or handle combustible dusts or combustible particulate solids.
NFPA 652 does NOT apply to:
- Storage or use of consumer quantities of combustible dusts on the premises of residential or office occupancies.
- Storage or use of commercially packaged combustible dusts at retail facilities.
- Combustible dusts displayed in the original packaging in mercantile occupancies and intended for personal or household use or as building materials.
- Warehousing of sealed containers of combustible dusts when not associated with an operation that handles or generates combustible dust.
- Combustible dusts stored or used in farm buildings or similar occupancies for on-premises agricultural purposes.
The annexes in this standard include tables with specific hazardous combustible dust characteristics, as well as an example dust hazard analysis (DHA), and other useful information.
NFPA 33, Standard for Spray Application Using Flammable or Combustible Materials
NFPA 33 applies to the spray application of flammable or combustible materials, and to the application of flammable or combustible materials, either continuously or intermittently by any of the following methods:
- Fluidized bed application methods.
- Electrostatic fluidized bed application methods.
- Other means of fluidized application.
NFPA 33 does NOT apply to spray application processes or operations that are conducted outdoors.
[Note: NFPA 33 should not be used to address combustible dust hazards at powder coating operations. 29 CFR 1910.107 is the vertical standard applicable at powder coating operations.]
NFPA 61, Standard for the Prevention of Fires and Dust Explosions in Agricultural and Food Processing Facilities
NFPA 61 addresses protecting life and property from fires, flash fires, and explosions posed by agricultural and food processing combustible dust.
NFPA 61 applies to:
- All facilities that receive, handle, process, dry, blend, use, mill, package, store, or ship dry agricultural bulk materials, their by-products, or dusts that include grains, oilseeds, agricultural seeds, legumes, sugar, flour, spices, feeds, dry dairy/food powders, and other related materials.
- All facilities designed for manufacturing and handling starch, including drying, grinding, conveying, processing, packaging, and storing dry or modified starch, and dry products and dusts generated from these processes.
- Seed preparation and meal-handling systems of oilseed processing plants.
A table in the annex of this standard provides agricultural dust characteristics.
NFPA 484, Standard for Combustible Metals
NFPA 484 addresses the production, processing, finishing, handling, recycling, storage, and use of all metals and alloys that are capable of deflagrating or exploding. It further has provisions for operations where metal or metal alloys are subject to processing or finishing operations that produce combustible powder or dust. Operations where metal or metal alloys are subjected to processing or finishing operations that produce combustible powder or dust include, but are not limited to, machining, sawing, grinding, buffing, and polishing.
This standard also applies to laboratories, recycling, and waste operations.
NFPA 484 does NOT apply to:
- The transportation of metals in any form on public highways and waterways or by air or rail.
- The primary production of aluminum, magnesium, and lithium.
The annexes to this standard include tables of metal explosibility properties.
NFPA 654, Standard for the Prevention of Fires and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids
NFPA 654 addresses all phases of the manufacturing, processing, blending, conveying, repackaging, and handling of combustible particulate solids or hybrid mixtures, regardless of concentration or particle size, where the materials present a fire, a flash fire, or an explosion hazard.
The purpose of this standard is to prevent explosion hazards involving combustible particulate solids, including hybrid mixtures, and to minimize the resulting damage from a fire or an explosion.
NFPA 654 does NOT apply to:
- Storage or use of consumer quantities of combustible particulate solids on the premises of residential or office occupancies.
- Storage or use of commercially packaged combustible particulate solids at retail facilities.
- Combustible particulate solids displayed in original packaging in mercantile occupancies and intended for personal or household use, or as building materials.
- Warehousing of sealed containers of combustible particulate solids when not associated with an operation that handles or generates combustible dust.
- Combustible particulate solids stored or used in farm buildings or similar occupancies for on-premises agricultural purposes.
NFPA 654 also does not apply to materials covered by other commodity-specific NFPA dust standards, unless otherwise noted in those standards.
The annexes in this standard include details on how to determine the hazards of the combustible dust in any given location. The annexes also provide examples of how to perform layer depth analyses to determine deflagration and explosion hazards. The annexes further include examples of explosion prevention and protection methods, including spark detection, extinguishing systems, and deflagration propagation isolation methods.
NFPA 655, Standard for Prevention of Sulfur Fires and Explosions
NFPA 655 may be referenced in conjunction with NFPA 654 and has provisions to eliminate or reduce the hazards of explosion and fire in the processing and handling of sulfur.
NFPA 655 does not apply to:
- The mining of sulfur.
- The recovery of sulfur from process streams, such as sour gas processing or oil refinery operations, and all its encompassed processes and operations, which include block melting, degassing, and forming.
- The transportation of sulfur.
The annexes in this standard include details on how to determine the hazards of sulfur dust in given locations. The annexes also include examples of how to perform layer depth analyses to determine deflagration and explosion hazards. The annexes further include examples of explosion prevention and protection methods, such as deflagration-propagation-isolation methods and guidelines for housekeeping.
NFPA 664, Standard for the Prevention of Fires and Explosions in Wood Processing and Woodworking Facilities
NFPA 664 has provisions on fire and explosion prevention and protection of industrial, commercial, or institutional facilities that process wood or manufacture wood products, use wood or other cellulosic fiber as a substitute for or additive to wood fiber, or that process wood, creating wood chips, particles, or dust. Woodworking and wood processing facilities include wood flour plants, industrial woodworking plants, furniture plants, plywood plants, composite board plants, lumber mills, production-type woodworking shops, and carpentry shops.
The provisions contained in Chapters 4 through 9 do NOT apply to woodworking operations that occupy areas smaller than 5000 ft2 (465 m2), and where dust-producing equipment requires an aggregate dust collection flow rate less than 1500 ft3/min (1500 CFM, 2549 m3/hr).
The annexes in this standard include details on how to determine the hazards of the wood dust in any given location. The annexes also include examples of how to perform layer depth analyses to determine deflagration and explosion hazards. The annexes further include examples of performance-based fire protection analyses for the design of buildings, separation distances, spark detection and extinguishing systems, and explosion protection methods (such as deflagration propagation isolation methods).
NFPA 850, Recommended Practice for Fire Protection for Electric Generating Plants and High Voltage Direct Current Converter Stations
NFPA 850 provides recommendations for fire prevention and fire protection for electric generating plants and high voltage direct current converter stations, except for:
- Nuclear power plants, which are addressed in NFPA 805; and
- Fuel cells, which are addressed in NFPA 853
Section 7.4 includes details for handling and controlling coal dusts and other combustible dusts at electric generating plants.
NFPA Industry Prevention and Protection Standards
NFPA 68, Standard on Explosion Protection by Deflagration Venting
NFPA 68 applies to the design, location, installation, maintenance, and use of devices and systems that vent the combustion gases and pressures resulting from a deflagration. In doing so, the structural and mechanical damage, and worker exposure, are reduced. NFPA 68 describes both how and when venting should be applied.
NFPA 68 does NOT apply to:
- Detonations, bulk auto-ignition of gases, or unconfined deflagrations, such as open-air or vapor cloud explosions.
- Devices designed to protect storage vessels against excess internal pressure due to external fire exposure or to exposure to other heat sources.
- Emergency vents for the pressure generated during runaway exothermic reactions, self-decomposition reactions, internal vapor generation resulting from electrical faults, or pressure generation mechanisms other than deflagration.
- Venting of deflagrations in oxygen-enriched atmospheres, or other oxidants, unless supported by specific test data.
NFPA 68 can be used in conjunction with NFPA 69, which covers explosion prevention and control measures. The choice of the most effective and reliable means for explosion control should be based on evaluating the specific conditions of the hazard and the objectives of protection.
Venting of deflagrations only reduces the damage that results from combustion.
NFPA 69, Standard on Explosion Prevention Systems
NFPA 69 applies to the design, installation, operation, maintenance, and testing of systems for the prevention and control (protection) of explosions by the following methods:
- Control of oxidant concentration.
- Control of combustible concentration.
- Pre-deflagration detection and control of ignition sources.
- Explosion suppression.
- Active isolation.
- Passive isolation.
- Deflagration pressure containment.
- Passive explosion suppression.
NFPA 69 covers provisions for installing systems for the prevention and control of explosions in enclosures that contain flammable concentrations of gases, vapors, mists, dusts, or hybrid mixtures. It provides basic information for design engineers, operating personnel, and authorities having jurisdiction.
Key elements of this standard include the following:
(1) Design system verification through testing.
(2) Design documentation.
(3) System acceptance.
(4) Management of change.
(5) Regular testing and maintenance.
NFPA 69 does NOT apply to the following conditions:
- Devices or systems designed to protect against detonations.
- Design, construction, and installation of deflagration vents as covered by NFPA 68.
- Protection against overpressure due to phenomena other than internal deflagrations.
- Chemical reactions other than combustion processes.
- Unconfined deflagrations, such as open-air or vapor-cloud explosions.
- Rock dusting of coal mines, as covered by 30 CFR 75 – Subpart E.
- General use of inert gas for fire extinguishment.
- Preparation of tanks, piping, or other enclosures for hot work, such as cutting and welding, as covered by 29 CFR 1910 – Subpart Q, NFPA 51B, and other standards for hot work.
- Ovens or furnaces handling flammable or combustible atmospheres, as covered by NFPA 86.
- Marine vapor control systems regulated by 33 CFR 154.
- Marine vessel tanks regulated by 46 CFR 30, 32, 35, and 39.
NFPA 77, Recommended Practice on Static Electricity
NFPA 77 applies to the identification, assessment, and control of static electricity for preventing fires and explosions. It provides guidance on controlling the hazards associated with the generation, accumulation, and discharge of static electricity by providing:
- Basic understanding of the nature of static electricity.
- Guidelines for identifying and assessing the hazards of static electricity.
- Techniques for controlling the hazards of static electricity.
- Guidelines for controlling static electricity in selected industrial applications.
This recommended practice applies to static electricity as it relates to gases, liquids, and solids. Annex G contains helpful information for grounding and bonding of typical equipment arrangements found in industry.
NFPA 77 does NOT apply to the control of static electricity and its hazards as they might affect electronic components or circuits, which have their own provisions.
NFPA 85, Boiler and Combustion Systems Hazards Code
NFPA 85 describes industry-recognized hazards in pulverized coal systems and related engineering controls. This standard applies to the design, installation, operation, maintenance, and training of boiler and combustion systems. Combustible dust is generated as a result of coal unloading, storing, transporting, pulverizing, feeding, and furnace combustion. Housekeeping is also briefly addressed in the Maintenance, Inspection, Training, and Safety section.
The provisions for pulverized fuel systems and equipment, including dust collectors, are addressed in Chapter 9.
[Note: NFPA 85 should not be used to address combustible dust hazards at coal-fired power plants. See 29 CFR 1910.269 as the vertical standard applicable at coal-fired power plants.]
NFPA 86, Standard for Ovens and Furnaces
NFPA 86 applies to Class A, Class B, Class C, and Class D ovens, dryers, and furnaces; thermal oxidizers; and any other heater system used for processing of materials. Provisions address explosion hazards related to furnaces.
Section 5.3 has provisions on explosion relief (with some exceptions) for fuel-fired furnaces and furnaces that contain combustible dusts. See also Annex A paragraph A1.1.7(1) regarding combustible dust hazards and controls for ovens and furnaces.
NFPA 86 does NOT apply to:
- Coal or other solid fuel–firing systems.
- Listed equipment with a heating system(s) that supplies a total input not exceeding 150,000 Btu/hr (44 kW).
- Fired heaters in petroleum refineries and petrochemical facilities that are designed and installed in accordance with API STD 560, Fired Heaters for General Refinery Services, API RP 556, Instrumentation and Control Systems for Fired Heaters and Steam Generators, and API RP 2001, Fire Protection in Refineries.
- Fluid heaters as defined in NFPA 87.•Electric arc furnaces and submerged arc furnaces.
NFPA Structural Standards
Several NFPA standards may be consulted to address structural hazards from fires and explosions, and have provisions for structures of varying types. However, in most cases where structural hazards are an issue, CSHOs should first refer to NFPA 101.
NFPA 101, Life Safety Code
NFPA 101addresses construction, protection, and occupancy feature to minimize danger to life from the effects of fire, including smoke, heat, and toxic gases created during a fire. This code establishes facility design criteria for egress to allow the prompt escape of occupants from buildings or, where pre-designated through employer training, into safe areas within buildings.
NFPA 101 also contains provisions for the design, operation, and maintenance of buildings and structures to ensure safe and adequate means of egress.
NFPA 5000, Building Construction and Safety Code
NFPA 5000 addresses the prevention or reduction of worker injury from building or structural failure during combustible dust events by incorporating certain building design features. This code has provisions to safeguard life, health, property, and public welfare, and to minimize injuries by controlling the permitting, design, construction, quality of materials, use and occupancy, location, and maintenance of buildings and structures, and certain equipment.
Factory Mutual Data Sheets
The following is a list of Factory Mutual (FM Global) Property Loss Prevention Data Sheets that can be useful to CSHOs when performing combustible dust inspections.
- FM Global 5-1, Electrical Equipment in Hazardous (Classified) Locations
- FM Global 5-8, Static Electricity
- FM Global 6-2, Pulverized Coal-Fired Boilers
- FM Global 6-9, Industrial Ovens and Dryers
- FM Global 6-13, Waste Fuel-Fired Boilers
- FM Global 6-17, Rotary Kilns and Dryers
- FM Global 7-0, Causes and Effects of Fires and Explosions
- FM Global 7-10, Wood Processing and Woodworking Facilities
- FM Global 7-11, Conveyors
- FM Global 7-17, Explosion Protection Systems
- FM Global 7-27, Spray Application of Ignitable and Combustible Materials
- FM Global 7-36, Pharmaceutical Operations
- FM Global 7-57, Pulp and Paper Mills
- FM Global 7-73, Dust Collectors and Collection Systems
- FM Global 7-75, Grain Storage and Milling
- FM Global 7-76, Prevention and Mitigation of Combustible Dust Explosion and Fire
- FM Global 7-85, Metals and Alloys
- FM Global 8-10, Coal and Charcoal Storage
- FM Global 8-27, Pulpwood and Outdoor Log Storage
These data sheets can be used alone or in conjunction with other standards to substantiate the review of combustible dust hazards.