Classes of Fires and Choosing Fire Extinguishers for Each
Fires require fuel, heat, oxygen, and a chain reaction to thrive. There are different classes of fires based on the fuel they are burning and therefore different types of fire extinguishers for each.
For example, water or wet chemical fire extinguishers may be sufficient in putting out wood fires but would be dangerous for ceasing an electrical fire from burning. Knowing the appropriate extinguisher for each hazard will ensure you are equipped with the correct fire protection for your business, facility, or home.
The Five Classes of Fires Based on the Fuel that Ignites Them
1. Class A: easily combustible materials like wood, paper, or cloth
2. Class B: gasoline, grease, oil, paint, and other flammable liquids
3. Class C: electrical fires caused by equipment, appliances, tools, and plug-ins that generate electricity
4. Class D: usually factory fires generated by metallic fibers such as titanium, magnesium, sodium, zirconium, lithium, and others
5. Class F or Class K: animal fats and vegetable oils that are used for cooking in kitchens and restaurants
Six Types of Fire Extinguishers
1. ABC Powder: As a multi-purpose extinguisher, ABC powder fire extinguishers are commonly used in households and businesses. It is safer than water, does not conduct electricity, and is ideal for gas and liquid fueled fires. The name itself means that it works best to extinguish all A, B, and C fires.
2. CO2: While some extinguishers may leave a mess, CO2 fire extinguishers get the job done with little to no residue left behind. The elimination of cleanup is ideal if electrical equipment catches fire, making it ideal for class B and C fires.
3. Wet Chemical: These extinguishers attack class K and class A fires the best, particularly in industrial kitchens and cafeterias. With any fire, there is always chance of reignition. Wet chemical fire extinguishers seal burning surfaces with a thick chemical foam made of potassium compound.
4. Water Mist: This is the most diverse fire extinguisher in terms of usage, as it covers all but class D (metallic) fires. Water is spewed in microscopic droplets, decreasing oxygen, cooling the fire, and removing the minerals of the fuel. Water mist extinguishers do not conduct electricity, making them safe even for combatting class C electrical fires.
5. Foam: Another common, but less versatile extinguisher is the foam fire extinguisher, which covers class A and B fires. The foam is mixed with water, acting as a cooling agent that suffocates the flames. It is ideal for fires fueled by flammable liquids and combustible materials.
6. Clean Agent: These fire extinguishers are considered gaseous fire suppressors. They are stored in cylinders as liquids but become gaseous when they come into contact with air. Gas (halon) particles do not remain in the atmosphere for long, therefore they are eco and human friendly. As an added bonus, they are non-conductive fire extinguishers do not leave behind residue and there is no cleanup, making them ideal options for class B and C fires.
Fire Protection Services in the Rocky Mountain Region
A working fire extinguisher is the immediate go to in an emergency. Rocky Mountain Air provides and supports your fire protection extinguishers to assure you the peace of mind needed to count on your extinguisher in an emergency. Based out of our Utah branch, we are able to service all of your portable fire extinguishers through testing, refilling, and certifications. Contact your local RMA branch today for any questions regarding fire extinguisher types and fire protection services for your business. We look forward to serving you!
