Fire Extinguisher Labeling
For ease of identification, labels A, B, C, D, and K (and, more recently, pictograms) indicate the type of fire on which one can use an extinguisher.
|A||Ordinary Combustibles||Fires in paper, cloth, wood, rubber, and many plastics require a water or dry chemical type extinguisher labeled A.|
|B||Flammable Liquids||Fires in solvents and other flammable liquids require dry chemical, Halon™, or CO² extinguisher labeled B.|
|C||Electrical Equipment||Fires in wiring, fuse boxes, energized equipment and other electrical sources require a dry chemical, Halon™, or CO² extinguisher labeled C.|
|D||Metals||Combustible metals such as magnesium and sodium require special extinguishers labeled D.|
|K||Cooking Oils and Fats||Wet chemical extinguishers specially designed to put out fires of cooking oils or fats are labeled K; unlikely to be needed in a laboratory setting.|
Most chemical laboratory fire hazards require multipurpose dry chemical extinguishers (ABC) located in hallways. “Gas” extinguishers containing carbon dioxide (CO2) offer a first defense against flammable liquids or electrical fires without leaving a powder residue that could harm electronic equipment. Halon™ 1211 fire extinguishers are no longer to be used on campus. If your lab has one, contact EHS so that it can be replaced.