How OTC Hearing Aids Are Different
Currently, there are two main categories of amplification products: Hearing aids and personal sound amplification products (PSAPs).
Hearing aids are medical devices that are intended to compensate for and correct hearing impairment. Hearing aids are already regulated by the FDA. Hearing aids are typically dispensed only after a hearing care professional performs a thorough hearing test and then programs the device to the specific hearing needs of each individual. The hearing care professional provides a comprehensive set of services such as hearing evaluations, counseling on the best hearing care solution, device fitting, education and training on how to use the hearing aid, and adjustment of the hearing aid to achieve the best outcome for the individual. In other words, hearing health professionals ensure that hearing aids are used safe and effectively.
PSAPs are consumer electronic products intended to increase environmental sounds for non-hearing-impaired consumers. They are not medical devices and are not regulated by the FDA for safety or effectiveness.
Given the difference in usage, the characteristics that make a good PSAP are very different than those that make a good hearing aid. PSAPs are designed to amplify all sounds and can be useful in specific situations only to consumers with normal hearing. Conversely, hearing aids use far more advanced technology to amplify speech from one specific direction and, at the same time, to reduce or cancel background noises coming from all other directions. These features can make a significant difference in speech intelligibility in any noisy environment.
Because of this, FDA has put out a notice warning consumer’s that PSAPs are not intended to compensate for impaired hearing or to address listening situations that are typically associated with and indicative of hearing loss. Rather they are intended for non-hearing-impaired consumers to amplify sounds in certain environments, such as for hunting, bird watching or other recreational activities.
Since PSAPs are not medical devices, today FDA has not defined safety and effective standards for this product category. The Consumer Technology Association has proposed performance criteria for what they define as “consumer products that provide personal sound amplification and/or enhancement to a user”. These criteria include a limit on the maximum output of 120 dB SPL and no limit on gain level.
As these standards are defined for consumer products and for occasional usage, they fall short of the necessary reassurance of safety and effectiveness for medical devices available over the counter. For example, both the World Health Organization and the U.S. Center for Disease Control recommend that sounds as high as 120 decibels can be safely listened to for only seconds per day. If we consider that hearing aids are typically worn for several hours a day, the risk is that even individuals with mild-to-moderate hearing loss may suffer additional hearing damage from prolonged over-amplification. As over-amplification occurs gradually over a long duration, individuals are unable to timely self-determine when prolonged exposure to over-amplification increases susceptibility to (further) damage their hearing ability. This situation is very similar to what has been noted with consumer listening products like headphones and earbuds, as documented by results of the National Health and Nutrition Examination Survey showing a significant increase in hearing loss among American adolescents who have sustained use of earphones.
In addition, it is worth noting that international organizations are taking steps to define requirements for safe listening also with regards to consumer products. Since 2009, personal music players in Europe must comply with the European Commission’s Directive that defines weekly dosage limits for exposure to ‘loud’ sounds from the use of personal music players (e.g. for sounds as loud as 80 dB(A) the permissible exposure time shall be limited to 40 hours per week). In 2019, the World Health Organization and the International Telecommunication Union have adopted similar standards in the context of their safe listening campaign.
Finally, OTC hearing aids by definition will be distributed over the counter, without the support of any hearing care professional. This means that consumers will be required to self-determine the level of hearing loss they have and if these OTC devices can provide help. Several studies conducted worldwide in the last twenty years show that only one-half to two-thirds of individuals can correctly classify their hearing loss. In particular, younger individuals tend to over-estimate their hearing loss; while older individuals tend to underestimate their hearing loss. This means it may be the case that young adults with normal hearing will try OTC hearing aids. If the maximum output allowed for OTC hearing aids is too high (consistent with consumer electronic standards), the risk is increased that these individuals will be over-exposed to loud sound and potentially develop noise-induced hearing losses.