Right for the Job: Types of Fire Extinguishers

When things get too hot you need to know how to cool them down, and this is especially true when it comes to putting out a fire. Fires can spark in an instant and spread in a blink, causing damage to property and endangering lives. If you asked most people what to do in a fire, they would roll their eyes and say grab the fire extinguisher. Yet fire education is only common knowledge to a point, because if you asked them what type of fire extinguisher they would probably stare back at you blankly. There are four distinct types of fire extinguishers that each are appropriate for different situations. Knowing which is best when can avoid disaster and save lives.

The four types of fire extinguishers are differentiated by which class of fire they can control. Class A fire extinguishers are meant to handle fires that are fueled by ordinary combustible material. Ordinary combustible material includes items like plastic, paper, cardboard, wood, and fabrics. Class A fire extinguishers use air pressurized water to douse the flames, and as such should never be used on any other type of fire as the water and oxygen will only make it spread. If you are unsure of the flames you are dealing with, opt to use a Class B or C fire extinguisher instead to keep from making the situation worse.

Class B fire extinguishers are used to put out fires that are fueled by combustible liquids, like grease, kerosene or gasoline. Class B extinguishers quell the flames by expelling a dry chemical powder or foam with a nitrogen propellant. The specific chemical can vary depending on the maker or model. There is some variety in Class B models, including the BC model that utilizes a corrosive sodium bicarbonate and the ABC model that uses monoammonium phosphate. Due to the caustic nature of the chemical in the BC model, all affected surfaces should be cleaned immediately after the fire is put out.

Class C fire extinguishers are designed to smote electrical fires. These are fires that occur on circuit breakers, wiring, electrical appliances like toasters, and electrical outlets. The most common form of material inside the extinguisher is carbon dioxide, although ABC and BC models from Class B may also be used on Class C fires. Carbon Dioxide extinguishers are made with a non flammable gas, and can also be used on Class B fires. Some fire safety professionals think that Class C extinguishers are not as effective as Class B extinguishers since they don’t leave a residue on the ignited surface which can prevent reignition. However, this is particularly why most people prefer Class C extinguishers.

Class D fire extinguishers are made to eliminate fires that are started and fueled by metals like titanium, sodium, and potassium. Class D extinguishers are typically only found in chemical laboratories and are generally filled with a substance that will snuff out a particular metal’s flame. For example, sodium chloride fire extinguishers work on alkali metals like titanium and potassium, while copper extinguishers quell flames from lithium fires. Class D extinguishers will not work on other types of fires.

As you can see from the difference between the four classes, knowing which type of extinguisher to reach for can make the difference between quenching the flames and fueling them. The best option for home owners is to keep a Class B ABC fire extinguisher on hand, particularly in the kitchen and during burning season to prepare for any type of incident and protect your property and loved ones.