With March 3rd being World Hearing Day, WHO-ITU (World Health Organization and International Telecommunication Union) released a new standard for safe listening devices on February 12th, 2019. As our group researches on improving hearing through array processing, we also think that preventing hearing loss and taking care of our hearing is important. Hearing loss is almost permanent, and there are currently no treatment for restoring hearing once it is lost. In this post, I will revisit the new WHO-ITU standard for safe listening devices, and I will also test how loud my personal audio device is with respect to the new standard.
Summary of WHO-ITU standard for safe listening devices
In the new WHO-ITU standard for safe listening devices, WHO-ITU recommends including the following four functions in audio devices (which is originally found here):
- “Sound allowance” function: software that tracks the level and duration of the user’s exposure to sound as a percentage used of a reference exposure.
- Personalized profile: an individualized listening profile, based on the user’s listening practices, which informs the user of how safely (or not) he or she has been listening and gives cues for action based on this information.
- Volume limiting options: options to limit the volume, including automatic volume reduction and parental volume control.
- General information: information and guidance to users on safe listening practices, both through personal audio devices and for other leisure activities.
Also, as it is written in the Introduction of Safe Listening Devices and Systems, WHO-ITU considers safe level of listening to be listening to sound with loudness under 80dB for a maximum of 40 hours per week. This recommendation is stricter than the standard currently implemented by OSHA (Occupational Safety and Health Administration), which enforces a PEL (permissible exposure limit) of 90dBA* for 8 hours per day with the exposure time halving with each 5dBA* increase in the noise level. NIOSH (The National Institute for Occupational Safety and Health) also has a different set of recommendations concerning noise exposure. They recommend an exposure time of 8 hours for a noise of 85dBA* with the exposure time halving with each 3dBA* increase in the noise level. With this recommendation, workers are recommended to be exposed to noise with 100dBA* for only 15 minutes per day!