Fire Extinguishers Class B Extingishers Fire Extinguishers
Fire Extinguishers
Fire extinguishers are classified by fire type. The A, B, C rating system defines the kinds of burning materials each fire extinguisher is designed to fight. The number in front of the A, B, or C indicates the rating size of fire the unit can extinguish.
To achieve a Class "A” rating, the extinguisher must be capable of putting out the wood crib, wood panel and excelsior (shredded paper) tests. Ratings are based on the size of the material that can be repeatedly extinguished.
Class B Extingishers
Class "B" LIQUIDS
Fire extinguishers with a Class B rating are effective against flammable liquid fires. These can be fires where cooking liquids, oil, gasoline, kerosene, or paint have become ignited. Two commonly used chemicals are effective in fighting these types of fires. Monoammonium phosphate effectively smothers the fire, while sodium bicarbonate induces a chemical reaction which extinguishes the fire.