Kitchen fires are the number one cause of house fires in the United States, and cooking oil is behind most of them. The pattern is almost always the same: a pan of oil heating on the stove, someone steps away, and by the time they come back the oil is smoking, then burning.
Cooking oil is combustible, and it will ignite on its own if it gets hot enough. Technically it is not "flammable" in the strict sense, because its flash point is well above room temperature. But every cooking oil has a smoke point, a flash point, and an autoignition point, and a stovetop can reach all three.
Smoke Point, Flash Point, and Fire Point
- Smoke point: the temperature where oil starts to break down and give off visible smoke. Roughly 350°F for butter and unrefined oils, 400°F to 450°F for vegetable, canola, and peanut oil, and up to 520°F for refined avocado oil.
- Flash point: the temperature where the vapor coming off the oil will ignite if it touches a flame or spark. For most cooking oils this is around 600°F.
- Fire point / autoignition: the temperature where the oil ignites and keeps burning with no spark at all, usually around 700°F to 800°F.
Here is the part that matters: a gas or electric burner on high can push a pan of oil past 700°F in a few minutes once the oil stops being cooled by food. If the oil is smoking, you are already most of the way there. If you see the surface start to shimmer and the smoke thicken, you have seconds, not minutes.
Why Grease Fires Get Out of Hand
Burning oil is a liquid fire, and liquid fires spread when the liquid moves. That is why the instinct to carry a burning pan to the sink is so dangerous: oil sloshes, and burning oil on the floor or on your arm is a far worse situation than a fire contained in a pan. It is also why water is the wrong answer. Water is denser than oil, so it sinks beneath the burning oil, flashes to steam instantly, and launches burning oil across the kitchen. That single mistake sends people to burn units every year.
What to Do if Cooking Oil Catches Fire
- Turn off the burner. Removing the heat source is the first step, not the last.
- Cover the pan with a metal lid or a baking sheet. Slide it on from the side rather than dropping it from above. Cutting off oxygen puts the fire out in seconds.
- Leave the lid on until the pan is cool. Lifting it early lets oxygen back in and the fire relights.
- If you don't have a lid, baking soda works on a small pan fire. Salt does too. Flour does not; it can flash and make things worse. See our article on whether baking soda puts out fires.
- A Class K or ABC fire extinguisher handles a stovetop fire, but aim at the base and expect a mess.
- If the fire has spread past the pan, get out and call 911. Close the kitchen door behind you if you can.
What Never to Do
- Never use water.
- Never move a burning pan.
- Never swat at it with a towel. Cloth fans the flames and can catch fire itself.
- Never pour oil down a hot sink or leave oil soaked rags in a pile. Oily rags can heat up and ignite on their own.
Preventing Cooking Oil Fires
Stay in the kitchen when oil is on the heat. Keep the burner at medium for pan frying and use a thermometer for deep frying, keeping oil below 375°F. Keep a lid within reach every time you cook with oil. Clean the stovetop and hood regularly, because built up grease is fuel for a fire that starts elsewhere. And if you deep fry a turkey, do it outdoors, well away from the house, with a fully thawed bird.
For more on kitchen fire risks, read where most house fires start and our guide to fire safety tips from a firefighter.
