Fire Extinguisher Types
The purpose of the various fire protection systems available today is to help reduce property damage and save lives by putting out fires quickly and effectively. No fire protection system is complete without fire extinguishers. These are some of the most important tools to have in your building because they put firefighting power in the hands of your attentive employees. Learn about the different types of fire extinguishers to help you purchase the correct ones for your building.
Extinguishers are classified based on the class of fire they are designed to put out. Here’s a look at each fire type.
- Class A fires consist of ordinary combustible materials, such as cloth, paper, cardboard, wood, and plastic. These fires are the most common and can occur in any home, office building, or other commercial setting.
- Class B fires occur when flammable liquids ignite. Gasoline, oil, propane, and kerosene burn readily, making these fires very dangerous and quick-spreading. Class B fires are likely to occur anywhere flammable liquids are found.
- Class C fires are electrical in nature, meaning there’s a risk of electrocution. Class C fires start when an overloaded circuit, overheated extension cord, or spark from a malfunctioning appliance ignites surrounding materials. It doesn’t matter what’s burning—if electricity started the blaze, it’s considered a Class C fire.
- Class D fires occur when combustible metals ignite. Highly reactive materials such as sodium, potassium, magnesium, and titanium combust easily, and water is often what starts the chain reaction. Class D fires occur in industrial facilities and laboratories.
- Class K fires break out in commercial kitchens. Cooking oil and grease burn at a higher temperature than other flammable liquids, so this special classification is reserved for restaurants, cafeterias, convenience stores, and other businesses with kitchens.
Fire Extinguishing Agents
Several firefighting agents are effective against specific types of fires. Here are several of your options:
- Dry chemical fire extinguishers usually contain a mixture of monoammonium phosphate and ammonium sulfate, chemicals that are effective against Class A, B, and C fires. For this reason, dry chemical extinguishers are often called multipurpose ABC fire extinguishers.
- Purple K fire extinguishers are rated for Class B and C fires. They are a type of dry chemical extinguisher often used by the oil, gas, chemical, and utility industries.
- Clean agent fire extinguishers use halocarbons to put out fires. Different types of clean agent extinguishers are effective against Class A, B, and C fires, or just Class B and C fires. They leave no residue behind after discharge, making them useful for settings with delicate electronics and documents.
- Carbon dioxide fire extinguishers are considered clean agent extinguishers. They contain sodium bicarbonate and sulphuric acid, which combine when you press the handle. A chemical reaction takes place, and carbon dioxide “snow” releases from the nozzle. This cuts off the oxygen supply to the fire, extinguishing the flames quickly and effectively. CO2 fire extinguishers fight Class B and C fires.
- AFFF (Aqueous Film-Forming Foam) fire extinguishers protect against Class A and B fires. They offer exceptional effectiveness against flammable liquid fires by creating a vapor barrier over the spilled fuel.
- Water mist fire extinguishers are effective against Class A and C fires. Because of their non-conductive hose and wand assembly, plus the use of de-ionized water, they are safe to use around electrical equipment up to 100,000 volts.
- Water fire extinguishers are rated for Class A fires only. They produce a soaking effect to put out deep-seated fires.
- Dry powder fire extinguishers are specifically designed to combat Class D combustible metal fires. A sodium chloride-based extinguishing agent forms a crust over the blazing metal to separate it from the oxygen it needs to burn.
- Wet chemical fire extinguishers put out high-temperature Class K fires. Standard dry chemical or Purple K extinguishers were once used to fight cooking fires, but these allowed for re-flash. Since 1998, highly effective wet chemicals have been used in commercial kitchen fires. Potassium acetate, potassium carbonate, and potassium citrate combine with grease and oil to create a soapy residue, a process known as saponification. This prevents re-ignition and makes commercial kitchens safer from fire. Wet chemical extinguishers are also effective against Class A and B fires.
Find the Right Type of Fire Extinguishers for Your Mid-South Building
If it’s time to buy new fire extinguishers for your business in Tennessee, Arkansas, or Mississippi, please contact State Systems Inc. for help making the proper selection. We offer a full range of brand-name extinguishers in various weights and sizes. In addition to assisting you with fire extinguisher sales, we also provide fire extinguisher training, installation, inspections, and more.
Contact State Systems online or call us at 866-308-5701 today for a fire extinguisher quote or to schedule fire protection services for your Mid-South business.
As director for a non-profit organization whose budget consists of federal grants, State Systems has been my personal choice to ensure my buses and buildings…Phyllis Olley Read More