Next time you come across an audiogram showing a mild to moderate high frequency hearing loss, remind yourself and be sure to communicate to your patient that research shows there is about a 50% chance they will not be aroused by their smoke detector during a residential fire. The majority of residential fire fatalities occur between 11 pm and 7 am when most people are sleeping and, therefore, not wearing their hearing instruments. In the absence of mandated frequency requirements, the majority of commercially available smoke detectors emit a 3,000 to 4,000 Hz signal. While signals generated by smoke detectors may objectively seem “plenty loud”, add to the mix the need for auditory signals to be on the order of at least 40 dB above thresholds to effectively arouse individual’s from sleep and suddenly there is a perfect storm just waiting to happen.
What’s an audiologist to do? First, educate yourself on the safety issues of how even a mild to moderate high frequency hearing loss interferes with smoke detector efficacy. Several resources are available including a relatively short but to-the-point article “Alarming Facts Audiologist Must Know” via Audiology Today (2010 Jan-Feb; 22(1): 40-5). In addition, a free-to-view webinar “Alarming Facts About Smoke Detectors” is also available via AudiologyOnline. Communicate this information to your patients so they become aware of this issue.
Second, whether they wear hearing instruments or not, be prepared to provide your patients with access to products incorporating critical signal components research shows to be effective in arousing individual with hearing loss during sleep. While there are a number of smoke detectors specifically marketed to the hearing-impaired population, look for bed-side products designed to work with existing residential smoke detectors products capable of emitting a 520Hz square wave with bedshaker. Currently, there are three product options available that meet this criteria: 1) the Lifetone HL Fire Alarm & Clock (Item# HLAC151), 2) Serene Central Alert Wireless System (Item# CA-360) with Audio Alarm Sensor (Item# CA-CX) accessory which is also sold as a bundle (Item# CA-360Fire), and 3) the SafeAwake Smoke and Fire Aid (Item# SART9V1). All three products detect the required T3-signals emitted by properly-installed residential smoke detectors sold in the United States and, in turn, generate a loud, 520Hz square wave signal at bedside. Both products come packaged with a bed shaker, offering a vibrotactileaccompaniment to the low frequency, square wave signal. For more information about either product, contact Oaktree Products toll free 800.347.1960 and ask for customer service. You very well could save a life.