New NFPA Combustible Dust Standards 2025
On December 6, 2024, the NFPA introduced a landmark shift in combustible dust safety standards with the release of NFPA 660: Standard for Combustible Dusts and Particulate Solids (2025). We interviewed Matt Coughlin, Owner and President of Baghouse.com, regarding how these new standards affect multiple industries.
— "What is NFPA 660, and why should we care?"
Matt: “If your facility handles anything dusty enough to be combustible, this new standard applies to you. NFPA 660 is the new consolidation of six different combustible dust standards. It replaces several older industry-specific standards, like NFPA 654, 61, 484, 655, and 664, and brings them together under one unified framework. The goal is to simplify compliance and create a consistent baseline for dust hazard analysis (DHA), explosion protection, housekeeping, ignition source control, and system design, regardless of the industry.”
— "So... what exactly does NFPA 660 cover?"
Matt: “In short: all the requirements for identifying, evaluating, and managing combustible dust hazards. It pulls together everything from hazard analysis to equipment design to training and emergency response. The first 9 chapters are based on what used to be NFPA 652, the old “Fundamentals” standard, while the remaining chapters dive into industry-specific details—like agriculture, woodworking, and metal processing. So whether you make cereal, shape aluminum, or sand furniture, there’s a chapter in the new standard that applies to your facility.”
Here’s a breakdown of the key features of NFPA 660 to help you navigate and understand this transformative standard:
- Fundamental Chapters (1–10): These chapters provide core guidelines for combustible dusts and particulates, aligning with the previous NFPA 652 standard (Chapters 1–9). Chapter 10 introduces new content.
- Future Topics (Chapters 11–20): These chapters are reserved for additional fundamental topics such as Fire Protection, Additive Manufacturing, and Nano Materials.
- Agricultural and Food Processing (Chapter 21): This chapter replaces NFPA 61, focusing on the unique requirements for agricultural and food processing industries.
- Combustible Metals (Chapter 22): Representing the previous NFPA 484, this chapter addresses risks and guidelines specific to combustible metals.
- Sulfur Standards (Chapter 23): Derived from NFPA 655, this chapter provides sulfur-related guidelines, now managed by the former NFPA 654 committee.
- Wood Processing (Chapter 24): This chapter supersedes NFPA 664, covering wood processing and woodworking standards.
- Other Material Combustible Dusts (Chapter 25): This chapter consolidates guidelines for all other particulate materials not specified in previous chapters, replacing NFPA 654.
- Committee Oversight: Committees for each specific area (e.g., Fundamentals, Agriculture) remain active to ensure accurate, industry-specific standards.
- Annex Material (A–Z): Expanded annexes offer supplemental information, including explanations, diagrams, and additional guidance. These are for reference only and not mandatory.
- Commodity-Specific Standards (Chapters 21–25): Include tailored requirements that address the unique risks and operational needs of specific industries, enhancing the foundational guidelines.
— "Is this standard wildly different from what we were doing before?"
Matt: “Not wildly. Most of the technical guidance is similar to existing standards, just reorganized, clarified, and modernized. The biggest updates? Clearer language, fewer contradictions, and improvements in the Hazard Management chapter—especially around process-specific equipment. Also, more detail on how to handle metallic dusts.”
— "Why did NFPA feel the need to consolidate all these standards?"
Matt: “Great question. Imagine trying to assemble IKEA furniture using six different instruction manuals written in different fonts and translated from Swedish by six different people. That’s kind of what combustible dust compliance looked like before. NFPA 660 streamlines the process. Now, you’ve got one clear document, with consistent definitions and guidance. “
— "Is NFPA 660 legally enforceable?"
Matt: “Technically, NFPA standards aren’t laws. But when OSHA or your local fire marshal adopts one by reference—or expects you to follow the “most current standard”—then yes, it effectively becomes enforceable. So, if you’ve got combustible dust anywhere in your facility, you should be planning around NFPA 660 going forward. Even if your inspector hasn’t mentioned it yet… you don’t want to be caught off guard when they do. It’s important to note however that your local regulations may differ from the NFPA standards, and you are responsible for complying with local laws regardless of whether they align with the standard.”
— "What does this mean for my Dust Hazard Analysis (DHA)?"
Matt: “If you’ve already completed a DHA under NFPA 652, good news—you’re still covered. NFPA 660 affirms that every facility handling combustible dust must complete a DHA and keep it updated. If you haven’t done a DHA yet? Well… this is your friendly reminder that now’s the time.”
— "Are there changes to dust collection system design in NFPA 660?"
Matt: “Not major ones. Most of the requirements for dust collection systems remain consistent, with some clarifications around explosion protection, fire isolation, and cleaning systems. If you were already designing to NFPA 652 or 654, you’re pretty close. Just make sure your documentation reflects the new standard and double-check anything specific to your industry. And no, NFPA 68 (deflagration venting) and NFPA 69 (explosion prevention systems) aren’t included in NFPA 660—they remain separate standards, so keep them in your compliance toolbox. And in case you are wondering, we do sell combustible dust equipment that is designed to comply with those standards as well. And if you need help understanding the standards or outfitting your facility to comply, we have a staff of experts who can help you.””
— "What industries are affected by this?"
Matt: “Pretty much any facility dealing with fine particulate matter that could become airborne—and flammable. That includes agriculture, food processing, wood, metal, plastic, rubber, pharmaceuticals, chemicals, and more.”
— "How do I start complying with NFPA 660?"
Matt: “Start by reviewing your current safety programs. Ask yourself: Have you done a DHA? Are your mitigation and suppression systems up to date? Are you training your people? Is your documentation current and aligned with NFPA 660? If you want to dig in a bit deeper on your own, you can start with some of our other posts on the basic requirements of combustible dust safety for dust collection systems. If you need help, this is where it pays to talk to experts—your equipment vendors and consultants like Baghouse.com who can guide you as well as provide the equipment”
See case study: Case Study – Combustible Dust Safety in Aerospace Manufacturing
— "Is this the final version, or should I expect more changes soon?"
Matt: “NFPA standards go through a three-year revision cycle. So yes, NFPA 660 will continue to evolve based on public input and committee feedback. The current version went into effect in December 2024, and we can expect updates in future editions—especially in the “reserved” chapters where new technologies (like additive manufacturing or nanomaterials) might be added. But for now? This is the go-to standard, and it’s worth getting familiar with.”
Final Thoughts
Standard for Combustible Dusts and Particulate Solids (2025)
NFPA 660 gives the combustible dust community a clear, consistent roadmap for staying safe and compliant. The intent is not to bury you in paperwork but to help prevent real-world tragedies from something as deceptively harmless-looking as dust.
So, grab a cup of coffee, open that PDF, and get to know NFPA 660.
