Will Your Children Sleep Through Your Smoke Alarm? Does It Have a Voice Feature?

“A mother’s recorded voice will wake a child and get him or her out the room much faster than a standard smoke alarm, a randomized trial has found.”

– Journal of Pediatrics (2018)

Researchers from the Center for Injury Research and Policy and the Sleep Disorders Center at Nationwide Children's Hospital found that a sleeping child was about 3 times more likely to be awakened by one of the three voice alarms than by the tone alarm. The alarms using the mother's voice awakened 86-91% of children and prompted 84-86% to "escape" from the bedroom, compared with 53% awakened and 51% escaped for the tone alarm.

The study also examined the effect of the different alarms on the amount of time it took the children to get out of ("escape" from) the bedroom.

In a real fire, seconds can make a difference. If a child wakes up but takes too long to leave a burning building, serious injuries or death could occur.

The median time to escape for the high-pitch tone alarm was 282 seconds -- nearly five minutes -- while the median times to escape for the voice alarms ranged from 18 to 28 seconds.

(Gary A. Smith, MD, DrPH, Thitphalak Chounthirath, MS, Mark Splaingard, MD. “Effectiveness of a Voice Smoke Alarm Using the Child's Name for Sleeping Children: A Randomized Trial.” Journal of Pediatrics. October 25, 2018)

These researchers examined characteristics of four different smoke alarms to determine which ones worked best to wake children. They tested three alarms that used the mother's voice in addition to a high-pitch tone smoke alarm commonly used in homes.

The study’s lead author, Dr. Gary Smith, who directs the Center for Injury Research and Policy at Nationwide Children’s Hospital in Columbus, Ohio, says …

“The thing that was most remarkable to us was to see a child sleep five minutes through a very loud high-pitched tone, but then sit bolt upright in bed when their mothers voice sounded through the alarm. We didn’t expect the difference to be so dramatic.”

The study’s co-author, Dr. Mark Splaingard, director of the hospital’s sleep disorders center, said the findings could help save lives in the future. Splaingard expains …

“Children are remarkably resistant to awakening by sound when asleep. We were able to find a smoke alarm sound that reduces the amount of time it takes for many children … to wake up and leave the bedroom.”

Sleep is a uniquely vulnerable time. Half of all fire deaths occur during the night. “Knowing which alarms work best can save lives,” says Splaingard. One night in 1998, Splaingard treated three kids with severe burns. He was puzzled because their house had a functioning alarm, but it hadn’t woken the kids up. Within a few years, Splaingard began his research to solve the problem.

Tests also showed that the mother did not have to say the child’s name for the voice alarm to be effective.

Children under the age of five were not tested because they are considered too young to rescue themselves in a fire, while teenagers do not have the same difficulty in waking up to smoke alarms. And, adolescents (older than 12 years) do not experience the same difficulty as younger children in awakening to a high-pitch tone smoke alarm.

In 2020, further research looked into what may be a better in response to a smoke alarm that uses a male voice, a female voice, a combination of a low-frequency tone plus a female voice (hybrid alarm), or a high-frequency tone. The results ...

“Use of the male or female voice or hybrid alarms in children's sleep areas may reduce residential fire-related injuries and deaths among children old enough to perform self-rescue. IMPACT:The male voice, female voice, and hybrid alarms were each significantly more effective than a high-frequency tone alarm in awakening children aged 5-12 years from slow wave sleep and prompting their performance of an escape procedure.

“There were no significant differences in the effectiveness of the male voice, female voice, and hybrid alarms when compared with each other. Use of these alarms in children's sleep areas may reduce residential fire-related injuries and deaths among children old enough to perform self-rescue.”

(G,A, Smith, T. Chounthirath, and M.Splaingard. “Comparison of the effectiveness of female voice, male voice, and hybrid voice-tone smoke alarms for sleeping children.” Pediatric Research. March 12, 2020.)

Further Support

Another reason why mom's voice works so well? Most smoke alarms blare out high pitched beeps at a frequency around 3,000 hertz. Studies have shown that alarms with lower pitches -- around 500 hertz, for instance -- work better at waking people up.

When smoke alarms were first developed, their inventors were more worried about detecting fire. They just assumed that a loud, high pitched noise would wake people up.

In fact, low frequencies would be “more effective for a whole range of vulnerable people,” says Dorothy Bruck, a sleep scientist at Victoria University in Melbourne, Australia. People who are older, or have trouble hearing, also respond better to lower-pitched alarms, she notes.

(Dan Garisto. “New smoke alarm tests a mother’s touch.” Science News For Students.

December 11, 2018.)

The National Fire Protection Association now recommends using low-frequency alarms, which can be 12 times more effective. Most households, however, still rely on devices that blare out high-frequency tones.

So, where do you buy a smoke alarm that allows the recording of a mother's voice? I have found alarms online with a prerecorded voice that blares “Fire! Fire! Fire!” But, I cannot find a device that allows recording a specific (customized) voice. It seems so simple. Could it be that regulations are so stiff that such a product is not yet available? Is there something else to consider. I'm sure time will tell.