Final answer:
Extinguishers are labeled with colors and symbols to denote the kind of fires they're suited to extinguish, with the NFPA system providing one such standardized method for identification.
Step-by-step explanation:
Extinguishers are marked using colors and symbols to help identify classes of fire that it's rated for. For instance, the National Fire Protection Agency (NFPA) 704 Hazard Identification System uses a diamond-shaped label where each colored part represents a different type of hazard. The fire extinguishers themselves are often categorized by different classes based on the types of fires they can extinguish, such as Class A for ordinary combustibles or Class B for flammable liquids.
The rating on each fire extinguisher provides important safety information and indicates what kind of fire it is equipped to handle. For example, a Class A extinguisher will be marked to signify it is suitable for ordinary combustible materials such as wood and paper, while a Class B extinguisher is marked for use on flammable liquids like gas or oil. It's crucial to choose the right fire extinguisher for the specific class of fire to ensure safety and effectiveness.