The National Fire Protection Association has conducted studies to determine the effectiveness of auditory smoke alarm signals in alerting sleeping adults 65+. The study used a variety of tones including a male voice alarm speaking words of warning (Fire, Danger, Wake Up).

The different auditory signals were played to study participants between 65 and 85 years old when they were in deep sleep. Each signal was played from 35 dBA to 95 dBA to sleeping participants who would press a bedside button upon awaking. The goal was to measure the auditory arousal threshold among older adults.

The study concluded that the current high-frequency T-3 signal currently used in smoke alarms is not effective for sleeping adults over 65. They found a mixed T-3 signal was effective at lower volumes than the high-frequency T-3 signal and that the male voice alarm was the least effective of all.

Key Recommendation: The high frequency alarm signal currently found in smoke alarms should be replaced by an alternative signal that performs significantly better in awakening most of the adult population, once the nature of the best signal has been determined.

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