Optimizing Emergency Awakening to Audible Smoke Alarms: An Update

Abstract

Objective: This review examines research on arousal from sleep in an emergency. It considers whether the current smoke alarm signal is optimal for waking those most at risk of dying in a fire and, if not, how it may be improved. Background: The fire fatality rate during the sleeping period is approximately three times greater than at other times. Method: Four key areas are reviewed: (a) the characteristics of four signals (high-frequency beeping, Temporal 3, voice, and naturalistic sounds); (b) how human characteristics alter arousal to different signals; (c) research comparing the effectiveness of different alarms in different sleeping populations; and (d) acoustical, methodological, and theoretical implications. Results: Significant risk factors for staying asleep include high levels of background noise, being a heavy sleeper, sleep deprivation, being a child, hypnotics, alcohol intoxication, and hearing impairment. The highfrequency beeping signal was significantly less effective than either a voice alarm or mixed-frequency beeping in waking selected at-risk groups. Conclusion: The alternative signals were more effective in arousing various groups of sleepers than was the high-frequency signal currently used in smoke alarms. Application: Replacement of the current smoke alarm signal with one of a lower frequency is likely to wake more people more quickly and save lives.

Auditory Countermeasures for Sleep Inertia: An Ecological Study Examining the Influence of Melody and Rhythm

“…Research has shown that musical stimuli with melodic features (instrumental, Vivaldi’s Four Seasons ‘Spring’ concerto) increases task performance when compared to silent conditions (41, 44), and it is posited by Riby (44) that this may be a consequence of music’s ability to increase arousal and enhance cognition. Additionally, the mode in which the music is sounded has been attributed to improvements in performance (45), and that pitches in the range of the female human voice (~ < 2500 Hz) may be more successful in arousing sleeping humans than male (90). The frequency range of the melodic treatment in this study resides between 1318.5 Hz and 2637 Hz.…”

Awakening of Sleeping People: A Decade of Research

“…The perceived increase occurs because the different frequencies activate different parts of the basilar membrane [34]. In addition, the multiple frequency peaks are less likely to be masked by ambient noise than a single frequency sound and lower frequencies penetrate walls and doors better than higher frequencies [28].…”

“…It was first specified by ISO in 1987 [26] and was first adopted in Canada in 1995, the USA in 1996 [27] and Australia in 2004 [28].…”

“…This review was expanded and updated by Bruck and Ball [28] Other research since 2001 has produced relevant findings. Proulx and Laroche [27] found that the T-3 sound was rarely identified as a fire alarm or evacuation signal and did not convey the need for an urgent response.…”

Epidemiology of burn injuries II: Psychiatric and behavioural perspectives

“…One recent study reports that women with persistent depressive symptoms were approximately 3.6 times more likely (95% CI ¼ 0.11-0.7) to not have a working smoke alarm (Chung, McCollum, Elo, Lee, & Culhane, 2004). However, one challenge to bringing the benefits of smoke alarms to potentially vulnerable populations is that hypnotics and alcohol have been shown to impair adults' ability to hear smoke alarms while sleeping (Bruck & Ball, 2007). Alarms that emit lower frequency signals appear to be more effective under conditions of alcohol impairment.…”