Business as usual...masked

We're heading back out of our homes after "shelter in place" and quarantines are slowly lifting, with a new adoption: the face mask Yes, there are many kinds, all different shapes, sizes and multiple guides on the internet including this one from the New York Times. While most of us are excited to venture back out to public spaces, for others, this new reality of face masks provides an enormous challenge to communicate. People with hearing loss, Deaf, and hard of hearing people often rely on lip reading to boost their understanding of speech. In fact, we all use visual cues to help us understand what we hear - take a look at this video, which demonstrates the McGurk effect (McGurk & MacDonald, 1975). So how much do face masks actually affect speech understanding? According to recent research: quite a bit. Not only do face masks block lip reading, they also degrade the speech quality and loudness. According to a simple test completed in Israel at the Alango Technologies lab (Goldin, Weinstein, & Shiman, 2020), masks can degrade the speech signal up to 12dB in some frequencies from a distance of 6 ft (2 meters). That means that even people with normal hearing may experience listening as if they have a slight hearing loss. The attenuation, or volume loss, was found to be mostly in the higher frequencies (2000-7000 Hz). These frequencies are the high pitch sounds - sounds such as a whistle, squeal or bird chirping. These high frequencies have also been found to contribute to our ability to understand speech better - for example, differentiating between "shower" and "tower" requires hearing and identifying the high frequency "sh" or "t" sounds (and mis-hearing could have embarrassing consequences). The good news? Regular surgical masks didn't have quite a large effect as N95 masks. This makes sense, considering N95 masks filter 95% of particles of 0.3 microns or larger, whereas surgical masks only filter 60-80% of particles. Therefore, it could be expected that N95 masks would also be more effective at blocking sound waves leaving the mouth. Since the majority of us use a cloth mask or simple surgical mask, there shouldn't be such a dramatic effect for most people, but for those with hearing loss, even a small volume reduction, can make the difference between hearing and mis-hearing. In addition to the fact that there are no additional visual cues for lip reading, this can present a huge challenge.

N95 masks can reduce sound volume by up to 12 dB

So next time we're out and about, whenever or wherever that might be, keep in mind that when wearing as mask, it's just slightly harder to hear you. As listeners, whether we're hard of hearing or with typical hearing, we should be prepared to ask for repetitions if we can't understand. And as speakers, we should be ready to slow down our speech, reduce background noise, and rephrase is we're not understood. For more tips on how to facilitate speech comprehension with masks see this post. These are tough times for everyone, so let's try our best to find some extra patience and understanding of one another. Stay healthy and safe!

References: Goldin, A., Weinstein, B., & Shiman, N. (2020, April 1). How Do Medical Masks Degrade Speech Reception? Retrieved from https://www.hearingreview.com/hearing-loss/health-wellness/how-do-medical-masks-degrade-speech-reception McGurk, H., & MacDonald, J. (1976). Hearing lips and seeing voices.Nature,264(5588), 746-748.

Parker-Pope, T. (2020, April 10). A User's Guide to Face Masks. Retrieved from https://www.nytimes.com/2020/04/10/well/live/coronavirus-face-masks-guides-protection-personal-protective-equipment.html#link-60e9a4e6