Many of the changes in the 2019 edition of NFPA 484 were made to align the document with NFPA 652, the new Standard on the Fundamental of Combustible Dust. These include:
- A new Ch. 7 was added on Dust Hazard Analysis.
- Ch. 4, General, includes material on objectives and compliances options to align with NFPA 652 as well as requirements on Management of Change and Personnel Protective Equipment.
- New chapters on Nanometals (Ch. 12) and Additive Manufacturing (Ch. 13) reflect emerging technologies and issues in the metals industry.
- Ch. 11, Powder and Dust Collection and Centralized Vacuum Systems, is rewritten to provide clarity.
- Ch. 15, Legacy Metals, consolidates the common requirements for aluminum, magnesium, niobium, tantalum, titanium, zirconium, and hafnium into a single location. (Material that is specific to one of these metals remains in the metal-specific chapters)
- Definitions in Ch. 3 are reviewed and updated to correlate with those in NFPA 652. Requirements in the code that are retroactive are indicated clearly.
- Material is added to the scope in Ch. 1 to clarify the application of the standard to mixtures of metals and other combustible nonmental dusts.
- Changes in Ch. 8 clarify and strengthen the requirements regarding static electricity.
- Changes are also made to the requirements for electrical area classification, referring to NFPA 70, National Electrical Code, but clarify that the committee does not agree with the definition of combustible dust found in NFPA 70. The committee also clarifies that the zone classification system is not to be used for metal dusts.