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Home Fire Hazards


Every 15 seconds, a fire department responds to a fire somewhere in the United States. A residential fire occurs every 66 seconds. There is one civilian fire death every 118 minutes. There is one civilian fire injury every 18 minutes.

The Nature of Fire
Home Inspection
Things to Think About


The Nature of Fire

Fires are likely to start in many places in the home including the kitchen, living room, bedroom and storage areas such as, the attic, basement, workroom or storeroom. Causes of fire include overheated or overloaded electrical wire, cigarette ashes, smoldering ashes in the couch, sparks from the fireplace, unattended outdoor fires and barbecues, appliances in poor repair and unattended cooking in the kitchen.

To understand the dangers of fire in the home, first understand the nature of fire. Fire occurs any time four elements are present - fuel, heat, oxygen and the chemical chain reaction. When these four elements are together, fire occurs. If any one element is removed, fire is prevented. These elements are collectively known as the "Fire Tetrahedron" or the "four faces" of fire.

Fuel, such as wood, paper or clothing (essentially anything that can burn) provides the energy for the fire. Oxygen, found in the air we breathe, is required for the burning process to occur. Heat provides a source of ignition, such as a match or a lighter, and causes the continued vaporization of solids such as wood in flammable gases. The chemical chain reaction or high molecular activity is needed to keep the fire burning. If any one of the four components is missing, fire cannot start. Removal of any one of these four causes fire to be extinguished. When fire occurs, an oxidation/reduction reaction takes place. This chemical term means a fuel, such as wood, is "reduced" in form in the presence of an oxidizing agent, oxygen and changes chemical make-up. Fire and heat cause the wood that is composed primarily of hydrogen and carbon molecules, to decompose thereby releasing energy in the form of more heat and flame. The wood is reduced and gives off carbon dioxide and hydrogen gases into the atmosphere and turns into ash (primarily carbon molecules).

Products with a high carbon and hydrogen content are the most effective fuels or "reducing agents." The most common of these are "complex hydrocarbons" such as gasoline, propane, butane and natural gas.

An oxidizing substance provides oxygen that is necessary for the burning or oxidations/reduction process to happen. The purest oxidizing substance is oxygen gas itself. Of the air we breathe, 21 percent is composed of oxygen. Thus, air is the most common oxidizing substance found. Other oxidizing substances include chlorine, bromide, iodine and ozone. For something to burn, it must first reach ignition temperature. Consider an unintentional fire in a trash can. A match that burns at more than 400 degrees Fahrenheit is dropped into a trash can. The embers ignite paper in the can and a fire begins. Once the fire starts, significant heat is generated. This heat causes unburned paper next to the flame to increase its molecular activity. The unburned paper vaporizes and turns to a gas. This flammable gas provides more fuel to the fire and it continues to burn.

The chain reaction means that the burning process must be allowed to continue in order for fire to burn. The collision of molecules in the oxidation/reduction process causes heat to build up, which sustains the combustion process.

Anytime just one of the four sides of the fire tetrahedron is removed, the possibility of fire is eliminated. A home fire inspection does just that. When a fire hazard is identified, one side from the fire tetrahedron has been removed. For example, we know that "Smokers Need Watchers." If a live cigarette ash is discovered behind a couch after a party and extinguished, the heat side of the fire tetrahedron is eliminated.

If a pile of rubble lying next to the house is discarded, the fuel for a potential fire is removed from the fire tetrahedron. If a grease fire is covered with a lid, oxygen is removed from the fire tetrahedron. If the fuel cells are removed from a nuclear reactor, the chain reaction is reduced.

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Home Inspection

One of the best ways to prevent fire in the home is to do a home inspection specifically looking for the fire hazards or preparing for emergency measures in case of a fire. Inspect your home one section at a time:

Kitchen
All electrical appliances and tools should have a testing agency label. Have the appliances repaired if they aren't working right. If an appliance gets wet, have it serviced.

Living room or family room

Bathroom

Bedrooms

Basement, Garage and Storage

Outdoors

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Things to Think About

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Last Modified on 11/09/2001 11:13:22