Fire extinguishers can be the first tool we reach for when a fire breaks out. A fire extinguisher is useful for stopping a small fire from spreading. Fire extinguishers are not only found at home. You’ll find them everywhere – in offices, restaurants and schools, as well as stores and airports. In many cases, public access to fire extinguishers is encouraged. The Occupational Safety and Heath Administration, for example, requires employers to make fire extinguishers readily accessible to their employees. You should always have a fire extinguisher in your car as an emergency tool.
A fire extinguisher is useless if you do not know how to use. Understanding the symbols on a fire extinguisher’s label is essential to using it correctly. These symbols indicate what types of fires an extinguisher is able to put out. It is important to know this information because the wrong extinguisher can make the fire worse. The good news is the most common fire extinguishers in American homes are multi-purpose units that are labeled with Class A, B, or C fires. This means that a single unit can be used to extinguish fires caused by everyday materials such as trash, flammable fluids, or even electrical equipment.
How do the A B and C symbols on an extinguisher work?
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Many home fire extinguishers have labels for more than one type of fire. If it has the symbols A, B, or C, then it is designed to handle each type. The Class A symbol (a triangular shape with “A”) indicates that the extinguisher is designed to handle fires caused by ordinary combustibles such as cloth, paper, plastics, and wood. These are the kinds of fires that produce ash. You’ve probably seen wood burn down to ash when you’ve used tools to maintain a campfire. This is the same process that a Class A fire extinguisher uses to put out materials. Ash is a good way to remember the class. You can identify this fire extinguisher by using the picture of the burning wood logs and trash along with the letter A in the triangle.
If you see a Class B symbol on a fire-extinguisher (a square with “B”), it means that the extinguisher can be used to put out fires started by flammable liquids or gases, like oil, grease paint, and alcohol. Water is not effective in putting out fires that are caused by flammable liquids. Water can actually make these fires worse. The Class C symbol (a circular with a “C”) indicates that the extinguisher can be used on electrical fires, even if the equipment is still plugged in. Water conducts electricity, which increases the danger. Never use it on a Class C Fire. Ammonium phosphate is used in most ABC extinguishers sold in the United States. It is a multi-purpose agent that can be used to smother, cool, and interrupt the chemical reaction for Class A, B, or C fires.
Do fire extinguisher icons always look the same?
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Labels for fire extinguishers are not always the same. In the U.S. the National Fire Protection Association, or NFPA, provides guidelines for the symbols on fire extinguisher labeling. This guidance is laid out in NFPA 170- Standard for Fire Safety and Emergency symbols. According to the These recommendations “provide standard symbols used to communicate fire safety, emergency, and associated hazards information. Using easily understood uniform symbols on labels and signs provides consistency, eliminates confusion, and improves communication.”
are based on the NFPA.
While there is no federal law mandating the use of these symbols on fire extinguisher labeling, many states adhere to the NFPA standard. Colorado and Connecticut, for example, have adopted NFPA 170 in their fire safety standards. Fire extinguishers are considered essential safety equipment for DIY projects at home, especially when working around tools or flammable material. If you’re in America, you can expect to see the same symbols on multipurpose extinguishers in offices and homes.
When you travel abroad, it’s a different story. The International Organization for Standardization has general recommendations for fire extinguishers. However, the way in which they are applied varies by region. You should always read the label of the fire extinguisher before using it to put out a fire.
