Are there different types of fire extinguishers? 

Yes, there are many different types of extinguishers for many different needs. To understand the types of extinguishers we must understand the types of fires. Fires can be defined by five different classifications. 

Fire Classifications

  • Class A: wood, trash, paper(ordinary combustibles)

  • Class B: flammable liquids: oil, gas, tars, lacquers, alcohols

  • Class C: energized electrical fires 

  • Class D: combustible metal fire: magnesium, potassium, titanium, plutonium, etc. 

  • Class K: cooking oils, grease, animal fats, vegetable oils etc.

Types of extinguishers

  • ABC dry chemical: These extinguishers are the most common and are perfect for class A class B and class C fires. Offices, kitchens, garages, vehicles: ABC extinguishers are optimal in eradicating almost every type of fire hazard. Due to versatility and affordability, dry chemical extinguishers are the gold-standard when protecting against fire danger. 

  • BC Dry Chemical: Unlike ABC extinguishers, BC extinguishers are only rated for class B and class C fires. A person may ask, “What’s the point of a BC rated extinguisher when I can purchase an ABC rated extinguisher?” Numerically speaking, a BC extinguisher weighing 10 pounds would have higher extinguishing capability against class B and C fires than an equally weighing ABC fire extinguisher. For this reason, BC fire extinguishers may be a better option where flammable liquids and electrical components are present.

  • PKP (Purple K Dry Chemical): Purple K extinguishers are especially good at fighting class B fires. They are also rated for class C fires but are more likely to be used In areas with high class B fire danger. Flammable liquid storages are an excellent place to mount a Purple K extinguisher. 

  • Class D Dry Powder Extinguishers: Class D extinguishers are used exclusively for fires involving combustible metals. Metals such as potassium, magnesium, titanium, and sodium burn at high temperatures, thus requiring an exclusive need for class D dry powder. Extinguishing agents such as water and carbon dioxide react violently when applied to combustible metal fires. Class D extinguishers work by encapsulating and smothering fire. Unlike ABC extinguishers which discharge quickly, class D extinguishers are designed to pile up softly creating layers which envelop fires. This process requires larger amounts of extinguishing agent than traditional fires. For this reason, these extinguishers start at 30 pounds for handheld units and larger for wheeled units.

  • Class K Wet Chemical Fire Extinguishers: Class K extinguishers are used to fight fires ignited from animal and vegetable fats commonly found in cooking oils and greases. While Class B extinguishers are effective in extinguishing flammable liquids, class K extinguishers have higher efficacy in commercial kitchens; the high-volume rapidly-spreading nature of commercial grease fires are best controlled by class K extinguishers and fire suppression systems. Class K extinguishing agent is expelled as a fine wet mist. Derived from an alkaline mixture of either potassium acetate, potassium carbonate, or potassium citrate, class K mist works by dousing vapors and eliminating the potential for re-ignition. 

  • Pressurized Water extinguishers: Stored pressure water extinguishers should only be used to fight class A fires or ordinary combustibles (wood, trash, paper, Ect.). Never use a water extinguisher on class B or C fires. Water acts as fuel to a grease fire (class b) and conducts electricity on and electric fire (class c). Water extinguishers work by cooling fuel below the temperature at which fires can actively burn or reignite.

  • Carbon Dioxide extinguishers: CO2 fire extinguishers are rated for class B and class C fires. They are not an optimal choice when fighting class A fires. CO2 extinguishers work by displacing oxygen and also cooling a fires fuel. Carbon dioxide inside a CO2 cylinder is so heavily compressed that it often expels bits of dry ice when being used. CO2 extinguishers require virtually no cleanup, thus making them an optimal choice for laboratories, flammable liquid storages, and mechanical rooms. A hydrostatic test is required on these extinguishers every five years to ensure structural integrity. 

  • Clean agent extinguishers: Clean Agents A.K.A. Halogenated extinguishers are designed to protect valuable assets specifically expensive computer systems, high-cost server rooms, and specialized machinery. These extinguishers are corrosion resistant, do not cause thermal shock damage, and are optimal for highly valued electronic/mechanical systems. Clean agents protect against class A, B, and C fires; they are paramount in the safeguarding of electronic and mechanical assets. 

In conclusion, it is always best to consult an expert when outfitting a business or residence with fire extinguishers. We look forward to creating a safer environment for your families, employees, customers, and friends.