During winter months, the risk for home fires increases significantly, so now is a good time to inspect home smoke alarms, say injury prevention experts at the University of Iowa.
"Fire risk rises as temperature falls," said Jingzhen (Ginger) Yang, UI assistant professor of community and behavioral health in the UI College of Public Health. "The risk of a house fire can increase by more than 20 percent during the winter months because of defects in heating appliances."
Nearly 65 percent of home fire deaths occur in homes without smoke alarms or smoke alarms that work properly, according to the National Fire Protection Association (NFPA), whose guidelines recommend changing smoke alarm batteries once a year and replacing alarms more than 10 years old.
Yang, fellow College of Public Health faculty member Corinne Peek-Asa and their colleagues studied smoke-alarm effectiveness in nearly 700 households in Keokuk County, Iowa.
"One reason why we conducted this study is that fire death rates are far higher in rural populations, including Iowa," said Peek-Asa, UI professor of occupational and environmental health and director of the UI Injury Prevention Research Center. "Yet we know much less about fire risk and prevention in rural areas than in urban areas."
In their baseline assessment of 691 Keokuk County homes, the UI researchers found that 80 percent of the homes had at least one functioning smoke alarm. However, only 25 percent of the homes studied had smoke alarms that would meet NFPA recommendations.
In most cases, Peek-Asa noted, the two key reasons homes didn't meet the guidelines were that they had too few alarms or they were not installed in the right places.
"In terms of location, a common oversight is not having a smoke alarm installed in the basement, where fires often start," she said. "Also, we found that some families placed smoke alarms directly in the kitchen when it's better to place the alarm in the egress away from the kitchen."
The number of recommended smoke alarms in a home will vary, Peek-Asa said, but alarms should be placed outside sleeping areas and entrances/exits. "In most of the single-story homes that we studied, three smoke alarms would have been the right number," she said.
When installed and operating correctly, smoke alarms can reduce fire deaths by 80 percent, Peek-Asa added.
Previous studies have found that most fire victims die from inhalation of smoke and toxic gases rather than as a result of actual burns. According to NFPA, most fire fatalities occur between 10 p.m. and 6 a.m., while people are asleep.
"Installation of smoke alarms at home is one of the important strategies of fire safety, which can significantly reduce the risk of dying in a fire," Yang said. "Families also need to have a fire escape plan and test fire extinguishers and smoke detectors according to the manufacturer's instructions."
She noted that lithium batteries are the best choice for smoke alarms.
"Although lithium batteries cost more than carbon-zinc or alkaline batteries, they last much longer -- up to 10 years -- and do not need to be changed every six to 12 months," Yang said. "In the long run, lithium batteries are more cost-effective in terms of remaining functional and reducing the risk of fire-related injury and death."