Did you know that the standard signal emitted by most commercially available residential smoke detectors falls between 3,000-4,000 Hz? Furthermore, the majority of residential fires occur between 11pm and 7am when most people are sleeping. According to Bruck & Thomas (2007), sleeping adults with a mild to moderate hearing loss respond to traditional smoke detectors about 50% of the time. Since hearing instruments are not typically worn during sleep, this creates a safety concern for our patients with hearing loss.
While there are a number of smoke detectors specifically marketed to the hearing-impaired population, one innovative product is the Lifetone HL Fire Alarm & Clock. This product was designed to work with existing smoke detectors already installed in the home. It is essentially a bedside fire alarm that also functions as an alarm clock. The product is equipped with a patented sensor that continually monitors sound. When a smoke detector is activated, the Lifetone HL will detect the smoke detector’s signal and, in turn, generate a loud, 520Hz square wave signal at bedside that has shown to be effective in waking 95% of individuals with hearing loss. This product also comes packaged with a bed shaker.
For more detailed information about hearing loss and smoke detectors, check out my article “Alarming Facts Audiologists Must Know” published in Audiology Today (Vol 22, issue 1) or the text-based course called “Alarming Facts About Smoke Detectors” published via AudiologyOnline. If you would rather hear all about it, AudiologyOnline has a free-to-view webinar called Alarming Facts About Smoke Detectors.
NOTE: since the publication of this post, the Lifetone HL Fire Alarm & Clock has been on a significant manufacturer backorder situation; it remains unclear as to whether or not this product will be commercially available. For another solution, please see the October 16, 2013 post on the Serene Central Alert CA-360.