Why not throw water on a grease fire?

passed along from my team

"... at Fire Fighting Training school we would demonstrate this with a deep fat fryer set on the fire field. An instructor would don a fire suit and using an 8 oz cup at the end of a 10 foot pole toss water onto the grease fire. The results got the attention of the students. The water, being heavier than the oil, sinks to the bottom where it instantly becomes superheated. The explosive force of the steam blows the burning oil up and out. On the open field, it became a thirty foot high fireball that resembles a nuclear blast. Inside the confines of a kitchen, the fire ball hits the ceiling and fills the entire room.

"Also do not throw sugar or flour on a grease fire. One cup creates the explosive force of two sticks of dynamite."

Time Required: You only have a few moments to either put out a grease fire or escape the house.

Here's WHAT TO DO:

1. 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.

2. 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.

3. 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 open flame.

4. Grease fires can also be smothered with baking soda, but it takes a lot of baking soda to do the trick. Unless the baking soda is easily accessible, it's usually easier to quickly find a lid.

5. 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.

Tips:

1. 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.

2. 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.

3. Treat burns only after the fire is contained or the building is completely evacuated. Read How to Treat a Burn for advice on burn treatment.

4. If clothes are caught on fire; STOP, DROP, and ROLL to extinguish them.

5. Reference: Hall, John R. Jr. "Home cooking fire patterns and trends." July 2006. NFPA Online. 20 Nov 2006