True, multipurpose dry chemical extinguishers are effective on class A, B, and C fires, not D and K
D and K fire
The different types of fire extinguishers are listed in classes according to which is appropriate for what type of fire. Below is an article which goes into the different classes of fire extinguishers.
Class B extinguishers are used for liquid fires, typically gasoline and oil fires. Extinguishers rated ABC will be effective against all three classes, but seldom as effective as a dedicated Class B extinguisher.
A, B, C, D and K.
There is one class of fire extinguisher for each of the 5 classes of fires: A,B,C,D,K. There are different mechanical types of extinguishers, based upon how their internal agent is expelled: contained pressure, external pressure cartridge, and manual pump. There are dozens of different types of agents found inside various fire extinguishers, ranging from ordinary air-pressurized water to many exotic gases and dry chemicals.
There are six classes of fires to define the type of fire, and most importantly, the type of fire extinguisher to use to put out the fire. Here are the fire classes and the types of extinguishers you should use: Class A - Solids (wood, paper, plastic) require water, foam, dry powder, and wet chemical extinguishers. Class B - Flammable liquids (fuel, oil, paraffin) require foam, dry powder, and CO2 gas extinguishers. Class C - Flammable gasses (propane, methane, butane) require dry powder extinguishers. Class D - Burning metals (aluminum, magnesium, titanium) require dry powder (M28/L2) extinguishers. Class E - Electrical items require dry powder or CO2 gas extinguishers. Class F - Cooking oils and fats require wet chemical extinguishers.
There are actually FIVE classes of fires now defined for purpose of determining the type of extinguisher to use: A, B, C, D and K.
classes
infectious diseases and types of chemicals
The chemicals that breakdown ozone are divided into classes. CFC's are the main ones that destroy it.
Cardio classes can not only be as effective as running in terms of a workout, but better for you. They can be lower-impact and still get your heart rate up and build endurance.
There is atype A (ordinary combustibles, leaving Ash),type B (flammable and combustible liquids),type C (conductive electrical equipment),type D (to put out burning metal), andtype K, used in commercial Kitchens for frying grease fires.