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FAQs About NFPA 652

Standard on the Fundamentals of Combustible Dust

What is NFPA 652?

NFPA 652, “Standard on the Fundamentals of Combustible Dust” was first developed in 2016, with the goal of creating standardized requirements for combustible dust safety across industries. The original standard developed a new regulatory component, Dust Hazard Analysis (DHA), which is a process that identifies and evaluates potential risks such as fires, flash fires, and explosions associated with combustible particulate solids within a facility.

What should I expect from the Update?

The key component of the 2019 update was setting a deadline for performing a DHA on existing processes and facilities. The 2019 update extended the deadline to September 7th, 2020, and includes new requirements for various process equipment. These new components include air moving devices (AMDs), air materials separators (AMS), sight glasses, duct systems, bulk storage enclosures, pressure protection systems, and various other types of equipment.

What are key components of a DHA?

A DHA must be updated every five years and typically includes:

  • Dust testing to identify the hazards of dust that are present
  • Identification and evaluation of potential fire, flash fire and explosion risks associated with the presence of one or more combustible dusts in a facility or process
  • Identification of hazards for each process, facility and components, as well as identification of safe operating ranges and safeguards
  • Data collection of system and performance requirements including the dust hazard testing
  • Recommendations for combustible dust management and documentation of all results to the client

What is combustible dust, and does it apply to my industry?

Combustible dusts are finely divided solids that present combustion and fire hazards under certain conditions. Combustible dusts can be found in most industries and come in many forms including (but not limited to):

  • Flours
  • Grains
  • Hops
  • Sugars
  • Charcoal
  • Lactose
  • Aluminum
  • Wood dusts
  • Rubbers, etc.

Many natural and synthetic organic materials can form combustible dust, as do some metal dusts and compounds.

Dust explosions form when an explosive dust is present, the dust is dispersed in the atmosphere in a concentration that can burn, the atmosphere supports combustion, an ignition source is present and when containment allows a pressure wave to build. When all these conditions exist, an explosion will occur.

How hazardous are combustible dust incidents?

The United States Chemical Safety and Hazard Investigation Board (CSB) concluded that between 1980 and 2005, there were 281 combustible dust incidents (not including grain-related dust explosions). These killed 119 workers, injured 718 workers, and severely damaged the industrial facilities affected.[1] OSHA’s Grain Handling Study reported that in the last 35 years there were over 500 explosions linked to grain handling dusts in the food and beverage industry alone. These resulted in 180 deaths and 675 injuries.[2]

In addition to the primary explosion that occurs under combustible dust circumstances, secondary, or fugitive dust explosions can be equally (if not more) lethal. Fugitive dusts are created and accumulated within a facility that produces combustible dusts. It is often trapped in unnoticed places, such as overhead beams and above ceilings. During a primary explosion, fugitive dust can ignite, producing a secondary explosion, which is oftentimes more destructive.

How can TÜV SÜD GRC assist me with my DHA needs?

TÜV SÜD GRC experts are licensed and experienced in Process Safety Management and DHA. We provide the most up-to-date and thorough assessments of your facility. We offer comprehensive Dust Hazard Analysis and Assessment services, from planning to completion, as well as explosion protection compliance services for international regulations. Our independent risk management services are unbundled from insurance providers, so you can be assured that the loss control inspections and services are customized to your needs, while meeting all regulatory standards.

[1] Chemical Safety and Hazard Investigation Board. “Combustible Dust Hazard Study, 2006-H-1”, November 2006.

[2] Occupational Safety and Health Administration. “Grain Handling Overview.” United States Department of Labor.


NFPA 652 Infographic

NFPA 652 Update

In a recent update to NFPA 652, a DHA will be required for existing processes and facilities by September 2020.

Learn More


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