5 Fire classifications
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Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.951(23) – Improved Guidelines for Marine Portable Fire Extinguishers – (Adopted on 5 December 2003) - Annex - Improved Guidelines for Marine Portable Fire Extinguishers - 5 Fire classifications

5 Fire classifications

  5.1 Fire classifications are generally indicated as A, B, C, D and F (or K). There are currently two standards, defining classes of fires according to the nature of the material undergoing combustion, as follows:

International Organization for Standardization National Fire Protection Association
(ISO standard 3941)* (NFPA 10)
Class A: Fires involving solid materials, usually of an organic nature, in which combustion normally takes place with the formation of glowing embers. Class A: Fires in ordinary combustible materials such as wood, cloth, paper, rubber and many plastics.
Class B: Fires involving liquids or liquefiable solids. Class B: Fires in flammable liquids, oils, greases, tars, oil base paints, lacquers and flammable gases.
Class C: Fires involving gases. Class C: Fires, which involve energized electrical equipment where the electrical non-conductivity of the extinguishing medium is of importance. (When electrical equipment is de-energized, extinguishers for class A or B fires may be used safely.)
Class D: Fires involving metals. Class D: Fires in combustible metals such as magnesium, titanium, zirconium, sodium, lithium and potassium.
Class F: Fires involving cooking oils. Class K: Fires involving cooking grease, fats and oils.
*Comite Europeen de Normalisation (CEN standard EN2) closely follows ISO standard 3941.
Parent topic: Annex - Improved Guidelines for Marine Portable Fire Extinguishers
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