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Sound Asleep
Research is needed to determine why children are sleeping through smoke alarms.
by Shelly Reese

NFPA Journal®, July/August 2003

• Studies launched
• More research needed
• Practice still the best solution
• Encouraging families to prepare

Marci Douglas still cries when she watches the videotape.

"I can't help it," she says. "It's so intense to watch. If it had been a real fire…" Her voice trails off. If she thinks about the "if," she'll start to cry again. If it had been a real fire, her son would be dead.

The video to which Douglas refers is a 2001 news feature story depicting sleeping children's responses to smoke alarms that WCCO-TV in Minneapolis produced with the help of the Bloomington, Minnesota, Fire Department. Marci's son Mitchell, then 10 years old, was one of four children WCCO tested to see how they would react to a smoke alarm in the night.

Their responses are frightening. One boy ran through the smoke rather than use a secondary exit. A little girl woke but didn't recognize the sound of the alarm. A third child didn't wake to the alarm and, when prodded by his mother to escape, simply froze.

However, watching Mitchell is what brings tears to his mother's eyes.

"I didn't think much about it before the test," Douglas says. "Mitchell is a smart boy. I thought he'd hop right out of bed. I thought there was a chance he might run right out the bedroom door and into the smoke, but it never occurred to me he wouldn't wake up."

He didn't. Not for almost 15 minutes.

Since WCCO conducted its news story, similar news stories have aired across the country, in places like Columbus, Ohio; Des Moines, Iowa; Milwaukee, Wisconsin; and Jackson, Mississippi. While these news stories lack the controls and specifications required for research, they have made one point clear: Children can sleep through smoke alarms.

According to published reports, researchers have long known that children sleep differently from adults and that their sleep is especially sound in the hours soon after they first fall asleep. The younger the child, the longer the deep-sleep phase is likely to last.

How that relates to smoke-alarm waking effectiveness has only recently been widely recognized, however, the many television news stories have raised interest in the existing formal studies. Because children 5 and under and adults 65 and older—for whom smoke-alarm waking effectiveness might also be an issue—are twice as likely as the general population to die in a home fire, the research has commanded the attention of everyone interested in fire safety in the home.

Studies launched
Last January, the U.S. Consumer Product Safety Commission launched a two-year study to investigate smoke-alarm waking effectiveness among children and the elderly, and the Fire Protection Research Foundation is seriously considering conducting a study of the issue of children not being awakened, according to Foundation President Rick Mulhaupt. To bring NFPA members up to speed on the issue, NFPA also invited Dr. Dorothy Bruck of Australia, the recognized world leader in research on the topic, to speak at its World Safety Conference and Exposition™ in Dallas this past May.

In addition, Underwriters Laboratories (UL) made the subject the centerpiece of its March 7, 2003 smoke alarm Standard Technical Panel meeting in Northbrook, Illinois, establishing two working groups to study the topic in detail.

The first group, composed of pediatric sleep experts, safety engineers, government officials, and manufacturers, was charged with gathering information and proposing future research designed to better understand the physiological and technical aspects of the issue. Such research might help lead to changes in the way smoke alarms operate and how they are installed and used. The second group, composed of UL staff, fire prevention and education specialists, and manufacturers, is developing information to effectively inform the public of smoke alarm and fire safety issues.

Such research and discussion are welcome, says Dr. Rita Fahy, NFPA's manager of fire databases and systems, who spoke on the topic at the Fire Suppression and Detection Research Application Symposium in Orlando, Florida last January, because the data available to date "raise more questions than answers."

Studies raise concerns
While less emotionally charged than the televised images of children sleeping through alarms, scientific studies published on the topic are perhaps more alarming because they confirm that this problem is neither a fluke nor an artifact of unrealistic test conditions.

Bruck, a psychologist at Victoria University in Australia, was the first to identify the problem. In her 1999 study published in the Fire Safety Journal, Bruck tested 20 children in Australia between the ages of 6 and 17 to determine their response to a 60-decibel alarm sounding at pillow level. She conducted her test twice and found 17 of the children slept through one or both tests. Two of the three who woke were 16 and 17 years old, among the older children in the sample. Indeed, for the children 15 and under, the reliable waking rate was only 5.6 percent. In contrast, Bruck found all of the parents woke when the alarms sounded.

In subsequent research, Bruck found that raising the sound level at the children's head made only a limited difference at best. In a presentation to the fourth Asia-Oceania Symposium on Fire Science and Technology in 2000, Bruck and fellow researcher Angela Bliss reported their findings from a study of 28 children between the ages of 6 and 15. In two tests, the children were exposed to an 89-decibel alarm; half slept through one or both tests. Among the 6 to 10year olds, that percentage climbed to 71 percent. When children did wake, they were groggy for several minutes, a factor that might well have impaired their ability to make life-saving decisions in a true emergency. Put simply, louder, closer alarms were unlikely to solve the problem.

While adults and some fire protection experts may be surprised by those numbers, kids themselves might not be.

Derrick Ethridge, fire prevention officer for the Loyalist Township Emergency Services in Ontario, Canada, decided to study the issue when children in the schools he visits told him they didn't think they'd hear an alarm if it went off.

"They kept telling me, ‘I don't think I'd hear it,' or ‘I sleep with my door closed,' or ‘I don't think I'd wake up,' " he recalls. "I suspected there was a problem just on the basis of what the kids were telling me, and I wanted to find out if that was true."

With the help of Professor Alistair MacLean of the Queens University Sleep Lab, the Canadian Hearing Society, the Limestone and Algonquin school boards, and the parents of 222 Loyalist Township sixth graders, Ethridge decided to conduct a test. Parents were asked to activate the smoke alarms outside their sleeping children's bedrooms between 9 and 11 p.m. on two separate nights in April 2002 and time how long it took the children to awaken. Tests were conducted once with the door closed and once with it open. The children knew they'd be tested but didn't know when.

The team found 31 percent of the children didn't wake up at all when the smoke alarm was activated, and 53 percent didn't react within the first minute. Ethridge later conducted random audibility tests in 22 of the homes. Testing once with the bedroom door open and again with it closed, he found sound levels in some cases dipped as low as 64 decibels.

"Some parents wrote back, ‘I took the damn smoke alarm off the ceiling, put it over my kid's head and he didn't move.' Or they said the alarm rang until the batteries went dead, and the child never woke up," he says. "They were definitely concerned."

As disconcerting as research such as Bruck's and Ethridge's may be, it must be considered in light of overwhelming data demonstrating smoke alarms' proven benefit. Since the early 1970s, when smoke alarms made their way into homes, residential fire deaths have been cut in half. Homes with smoke alarms—whether or not known to be operational—have a death rate 40 to 50 percent lower than the rate for homes without alarms, says Dr. Fahy.

Today, the overwhelming majority of fatalities take place in homes that aren't equipped with alarms or in homes where the equipment is broken, dismantled, or missing a battery. Half of the people killed in home fires each year die in the 5 percent of homes that don't have smoke alarms. Of the fatalities that do take place in homes equipped with alarms, half occur in one-third of the cases in which the smoke alarm doesn't sound.

More research needed
The fact that children are sleeping through alarms must be studied against this backdrop, Fahy says, and the magnitude of the problem can't be diagnosed without additional research.

"Of all home fire deaths, we're talking about a subset of the 25 percent that occur in homes with operable alarms," she says, "and we need to know more about those cases." 

For example, how are people alerted when nighttime fires occur? Are alarms waking parents who then shuffle their children out of the house? If so, are the alarms accomplishing their aim by alerting parents and enabling the family to put its escape plan into action?

While the media focus has been on children sleeping through alarms, what about older residents who are most likely to have hearing loss and are more likely to live alone or with other seniors? Would different types of alarms, such as voice notification or a lower frequency, achieve better results? Would interconnecting alarms as is already required for new construction by NFPA 101®, Life Safety Code®, make a substantial difference?

Without at least some of that information, it's impossible to draw actionable conclusions from existing studies, demonstrations, and news reports, Fahy says.

John Drengenberg, UL's manager of Consumer Affairs and moderator for the March panel discussion on the topic, voiced the same sentiment.

"Based on what we heard from pediatric sleep experts and fire prevention officials, there might not be a single answer to this complicated issue," he says.

Practice still the best solution
While officials study the issue and try to ascertain how best to address it, NFPA President Jim Shannon emphasizes that parents shouldn't let their concern about the issue distract them from the larger issue of fire safety.

"If parents conclude from the demonstrations that they don't need some alarm protection, they'll be dead wrong," he says. "The fact is, smoke alarms do work. What remains to be seen is if we can make the technology better and use it more effectively."

Lee Richardson, NFPA staff liaison for NFPA 72®, National Fire Alarm Code®, advises not to "throw the baby out with the bathwater."

"People shouldn't get tunnel vision," he says. Instead, they need to focus on maintaining and testing their smoke alarms and practicing their home escape plans.

NFPA 72 contains requirements for the type of sound pattern an alarm emits and how loud it needs to be throughout the home and especially in sleeping areas. Although the location of smoke alarms in homes in any U.S. community is determined by local building codes, NFPA 72 includes location requirements typical of those usually found in these codes.

While recent news coverage has raised awareness, NFPA's technical committees aren't yet considering changing the codes, Richardson says. The next edition of the National Alarm Code is scheduled for publication in 2006. Changes may be forthcoming, if research identifies areas where significant and meaningful improvements could be made.

As Shannon notes, however, the effectiveness of smoke alarms has as much to do with practices in the home as it does with codes and standards.

"As safety groups, including NFPA, explore the issue, there's still very good reason to remain confident about the role of smoke alarms in home fire safety systems," he says. "In the near term, the lesson parents should take away from these news broadcasts is that they won't know how their children will react to the smoke alarm until they've tested their response to it. Home fire drills are essential."

Evidence indicates that familiarization with the sound of the alarm and practicing escape drills holds promise. Bruck cites research indicating that adult subjects who were primed to respond awakened 90 percent of the time. Those who weren't woke only 25 percent of the time.

Although it wasn't a research project, families who participated in the WCCO broadcast had a similar experience. After the four children failed the initial test, their parents talked to them about fire safety. They also laid out home escape plans and practiced them. Marci Douglas discussed fire safety with Mitchell, then activated the smoke alarm with a broom handle so her kids would recognize its sound during an emergency.

When WCCO repeated the drill several weeks later, all four children awoke and carried out the drill to the letter.

Encouraging families to prepare
Judy Comoletti, assistant vice president of NFPA's Public Education Division, not only emphasizes the importance of developing and rehearsing home escape plans, but suggests that parents activate their smoke alarms and conduct their drills at night, so they can better gauge the reaction of everyone in the household. Children and the elderly aren't the only ones at risk of sleeping through an alarm, she notes. Sleep-deprived college students, shift workers, teenagers, the hearing impaired, and anyone taking sedating medication, alcohol or drug-impaired individuals, might conceivably be affected, as well.

"Every family should know who will—and won't—wake up at the sound of the alarm so they can accommodate any special needs," she says. If someone is hard to rouse, Comoletti suggests installing additional hard-wired, interconnected alarms in every bedroom. If this doesn't work, she encourages families to design an escape plan that assigns an adult who awakens easily to rouse the sound sleepers.

"We all think we know our kids so well, and we think we know how they will react to A, B or C," says Douglas. "We think they're so smart they'll know just what to do. However, the reality is you don't know at all until it happens. You have to practice. It's like helping your kid prepare for a spelling test. You have to drill them."

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