Perfluorohexanone for Clean Fire Suppression: Mechanisms, System Design, Applications, and Future Directions

ABSTRACT Clean fire suppression is being reshaped by the phase‐out of halons and high‐GWP hydrofluorocarbons. Perfluorohexanone has emerged as a leading alternative because it combines zero ozone‐depletion potential, very low global warming potential, low toxicity, and high extinguishing efficiency at practical design concentrations. This review synthesizes recent progress in perfluorohexanone fire suppression from the mechanism to the system design and application. Its suppression action is discussed in terms of rapid vaporization, flame cooling, and chemical inhibition of radical chain reactions, followed by engineering requirements for total‐flooding systems under NFPA 2001 and ISO 14520. Application evidence is reviewed across data centers, energy‐storage systems, aviation, transportation, cultural heritage protection, and other mission‐critical settings. Particular attention is given to residue‐free discharge, electrical compatibility, occupant safety, and field deployment constraints. Emerging strategies, including inert‐gas blending, water‐mist coupling, localized delivery, and microencapsulation, are evaluated for their potential to reduce agent demand, improve distribution, and address concealed or high‐risk fire scenarios. Remaining challenges include battery thermal runaway, HF byproduct management, two‐phase discharge modeling, enclosure nonuniformity, and long‐term system reliability. The review identifies research priorities linking combustion chemistry, hydraulic design, standards development, and full‐scale validation to support safer and more sustainable use of perfluorohexanone.