Residential Building Electrical Fires – Part 2

Residential Building Electrical Fires

Each year in North America, hundreds of people die and thousands are injured in accidents involving electrical fires. Most of these incidents can be prevented by following simple electrical fire safety rules. Although some of these fires are caused by electrical system failures and appliance defects, many are caused by the misuse and poor maintenance of electrical appliances, incorrectly installed wiring, and overloaded circuits and extension cords.

The Residential Electrical System Aging Research project was launched by the Fire Protection Research Foundation to study how the age of wiring, outlets, junctions, and other connectors affects the pattern of electrical fires in homes. One objective of the study is to make improvements to the National Electrical Code (NEC) (National Fire Protection Association (NFPA) 70) and through the building codes adopted by local and State jurisdictions around the country. Already, changes in wiring practices dictated by better electrical codes and the required use of smoke alarms have made new construction safer.

Residents demand higher levels of electrical energy to power their homes and appliances than they did in the past, and new homes are built to meet this demand for multiple televisions, phones, hairdryers, microwaves, washers and dryers, etc. As the consumers’ electrical demands increase, so does their expectation that their homes will supply adequate power to meet these. They meet their needs by adding more circuitry (and circuit breakers in blank spots on the breaker panel, or even another circuit breaker box) and outlets to accommodate their purchases. If an outlet is added to an existing circuit, then the load easily can be more than the wiring originally was designed to conduct- perhaps decades ago. Local experts say all of the above are signs of possible problems.

Electricians say older homes are more likely to have problems and electrical systems in an older home should be upgraded and inspected at least once in its lifetime. If not upgraded, an older system may not be able to handle the modern heavier electrical load, which may cause problems such as the wires' heating up. But even new homes could have issues. Experts said many of the problems are homeowner-created. Here are some ways to avoid common problems: 1. Minimize extension cord use and only use temporarily. 2. Use the correct wattage in lamps and light fixtures (table lamps and many light fixtures generally can only handle a 60-watt bulb, but refer to the instructions). 3. Keep receptacle outlets updated – they shouldn't be warm to the touch or be loose. 4. Combustibles near light fixtures in closets should be avoided. 5. Use the correct size replacement fuses or circuit breakers, and in particular use the correct amperage for the circuit. 6. Use licensed electricians and obtain permits for electrical work when required. 7. Make sure an electrician you hire has a license number, which is required by state law. Not all "handymen" are licensed. One way to tell is those not licensed are generally cheaper, but they can pose a significant danger.

What these consumers really do is create unseen hazards in their homes. Inside the walls, wiring is heating and damaging its own insulation, wood frames are being charred by high-wattage light bulbs too close to ceilings, and fixture wattage ratings are being exceeded. But as long as the lights come on and the appliances start, the consumer remains unaware of the danger—until a fire starts.

The functional and structural areas of the home are the most likely to experience electrical fires. Included in the functional category are bedrooms, dining rooms, kitchens, bathrooms, laundry areas, and the like. 15%  of residential building electrical fires start in a bedroom. The bedroom also is the leading area of fire origin for fires with injuries and dollar loss—bedrooms account for 30% of residential building electrical fires that result in injuries and 16% of residential building electrical fires that result in dollar loss. Structural areas of the home include areas such as crawl spaces, attics, walls, porches, and roofs. Attics, the second leading area of fire origin, account for 11% of residential building electrical fires. Over a quarter of all residential electrical fires start in these two areas. While fewer residential electrical fires start in lounge areas (family rooms, living rooms, and the like), these fires result in nearly a third of the deaths (31%).

By far, building structural components is the largest category of items first ignited in residential building electrical fires. Structural components include structural member or framing, insulation, trim, wall coverings, flooring, and the like. Of these components, structural framing (usually wood) accounts for 17% of residential electrical fires. Insulation and interior and exterior wall coverings (e.g., paneling, wallpaper, siding) account for an additional 18% of residential electrical fires. However, the leading item first ignited in residential electrical fires is the insulation around electrical wires and cables. At 30% of residential electrical fires, it accounts for nearly the entire general materials category. Together, insulation around electrical wires and structural member/framing account for 38% of all deaths from fires in residential buildings.

Heating, lighting, and cooking activities are highest in winter and so, too, are the occurrence of indoor fires stemming from electrical problems. Throughout most of the year, the pattern of residential electrical fires is consistent, but occurrences peak in December and January, accounting for 22% of all such fires. In the winter months, the relative humidity within the walls of a typical home can be very, very low and can turn wood wall framing into kindling, easily ignited by an arcing current. Fire deaths also are high in these months, but March and October, still dry months, both have similar peaks. Summertime has the lowest incidence of deaths resulting from electrical fires in the home. The numbers shows that late afternoon and evening are the most likely time for electrical fires to occur in residences. But it is the hours before dawn, between 3 and 6 in the morning, when deaths are most frequent.

Wiring and electrical components have a life expectancy that does not always equal the life cycle of the building. As the electrical equipment wear out, fires are more probable. Electrical wiring with its various components is by far the major culprit in residential building electrical fires. Lamps and other lighting and cords and plugs also present severe problems.

What are signs there may be an electrical problem at your house? Here are few signs: 1. Your lights are flickering. 2. A plug is loose in an outlet, or the area around the outlet is warm. 3. You feel a tingle or shock when you touch an appliance (or while in the shower). According to experts, if you notice an electrical fire, you should turn off your power (if it's safe) and leave your house. Then call 911 to report the fire.