Grease fires happen when collections of oil or grease on a stove, oven or fryer get hot enough to ignite. Grease fires are extremely dangerous because the fuel source (the grease) is a liquid, and easily splashed if you try to spray water on it. Grease fires burn very hot and can quickly spread to cabinets or other flammable areas of the kitchen.
The most important thing you can do to prevent a fire in the kitchen is to stay put.
The NFPA reports that unattended cooking is the leading cause of home cooking fires. Stay by the stove and be prepared for flames.
On the other hand, once a fire starts: if you can't put it out immediately, leave. Sticking around to try to extinguish a fire after the occupants are out is not something you try unless you are the fire department. Even then, I hope you're using proper safety equipment and procedures.
DO NOT USE WATER ON A GREASE FIRE! (see Tips) Start evacuating everyone from the building. Fires spread extremely fast and can overwhelm victims in minutes. Treat burns only after evacuating the building.
Call 911. There's no reason to wait, and the fire department can always go back to the station if you are able to get the fire out without help.
The easiest way to smother a grease fire is to cover it with a pan lid. Be careful with glass lids; they can break from the extreme heat of an open flame.
Grease fires can also be smothered with baking soda, but it takes a lot of baking soda to do the trick.
A dry chemical fire extinguisher will also work, but it will contaminate your kitchen and food. Class K fire extinguishers are available to put out grease and other kitchen fires, but they are usually only found in commercial kitchens.
DO NOT PUT WATER ON A GREASE FIRE! This can not be stressed enough. Pouring water on burning grease or oil will not extinguish the fire. It will only cause the burning oil to splash, spreading the grease fire around.
DO NOT TRY TO CARRY THE FIRE OUTSIDE! Trying to carry a pot or pan full of burning oil will just slosh and splash the grease fire.
Treat burns only after the fire is contained or the building is completely evacuated.
If clothes are caught on fire; STOP, DROP, and ROLL to extinguish them.