Written by Jan L. Mayes, MSc, Audiologist (Retired)
This article was originally published in Communique, the Speech-Language Audiology Canada blog: https://blog.sac-oac.ca/protecting-hearing-for-life/
The theme of World Hearing Day 2022 is, “To hear for life, listen with care.” In our modern world, harmfully loud recreational sound exposures have become commonplace. My co-author Daniel Fink, MD, Board Chair of The Quiet Coalition, USA, and I published papers on non-occupational noise exposures in Proceedings of Meetings on Acoustics (Fink & Mayes, 2021; Mayes & Fink, 2021).
Noise is defined objectively as harmful acoustic energy, whether the sound is wanted or unwanted. Personal listening with headphones or earbuds may be the leading source of recreational noise doses, especially for children, teens, and young adults who have grown up using this technology. Other common sources include social, entertainment, and sports venues frequented by all ages.
Non-occupational exposures are so widespread that noise-induced hearing loss (NIHL) is becoming a young person’s disease. Besides other noise prevention, safer
listening is crucial to protecting everyone’s hearing for life.
How loud is too loud?
The Speech-Language & Audiology Canada (SAC) NIHL brochure (2019) includes the evidence-based non-occupational daily average exposure limit of 70 dBA (decibels, A-weighted). This does not consider noise-induced impairments which typically precede NIHL: tinnitus, hyperacusis or decreased sound tolerance, and/or auditory processing disorders such as speech-in-noise performance deficits despite hearing thresholds within the normal range (Pienkowski, 2021).
Noise-sensitive populations need greater protection, because they are at a higher risk of impaired hearing from the same or lower exposures (WHO, 2018). These groups include infants to teens exposed during critical periods of peripheral and central auditory system maturation (Eggermont, 2013).
Noise= Amplified and/or manufactured sound energy that exceeds public health recommended community, environmental, and night noise limits.
Noise Dose= There is no such thing as a “safe” noise dose, no matter how short the exposure or listening time (EPA, 1972; WHO, 1999-2019).
dB= decibels typically measured in Sound Pressure Level, dBA, or dBC (e.g. LAeq,24-hour; LCeq,24-hour). Time-weighted averages should never be used in public health (e.g. dB Lex,8-hour or 40-hour).
Note: Exposures <30-35 dB may be needed to protect total health e.g. bedrooms, classrooms, hospital rooms, nature preserves.
Safer Personal Listening
In 2020, the World Health Organization (WHO) estimated that about 50% of young people aged 12 to 35 are at risk of NIHL from using personal audio systems (PAS), over 10 million Canadians (Statistics Canada, 2021).
Typical PAS user volumes range from 75 to 105 dBA. Using PAS is like bringing a rock concert to the ear canals. Boyle’s Law, where pressure is inverse of volume, indicates risk is likely higher from acoustic energy delivered at children’s smaller, shorter ear canals.
Hearing protective approaches include avoiding or limiting PAS use in childhood, turning any safer listening features, intensity limits or parental controls to the lowest sound exposure possible, never using volume booster apps, and choosing well-fitting headphones or earbuds with noise-canceling or isolating features, especially if listening in ambient environmental noise, e.g. taking public transit.
Consumers should beware of headphones with 85 dBA or higher noise limits, falsely advertised as “safe” for children. PAS-compatible earplugs and earmuffs are available, e.g. safer personal listening in occupational noise.
Generally, using the lowest comfortable PAS volume setting below 50% is safer for hearing. A 20% to 45% volume is usually a comfortable range for typical hearing PAS users, with unlimited listening time.
The Scientific Committee on Emerging and Newly Identified Health Risks (2008) identified PAS use >1 hour daily > 50% volume for <5 years is associated with impaired otoacoustic emissions and extended high frequency hearing loss, with NIHL expected to develop with >5 years of use. Swierniak et al. (2020) found 11-year-old PAS users who listened about an hour daily at around 50% volume reported more tinnitus than non-users.
About 50% to 60% volume settings produce approximately 70 to 80 dBA PAS sound output (Breinbauer, 2012). These acoustic exposures may cause tinnitus, hyperacusis, and speech-in-noise performance deficits with no associated NIHL, especially in children and teens (Eggermont, 2013).
Exposure above 60% is higher risk. Compared to unexposed populations, estimated risk of hearing loss in unprotected workers aged 18 to 65 is 1% for 80 dBA, 8% for 85
dBA, and 25% for 90 dBA daily average noise exposure (NIOSH, 1998). Individuals–or their parents–should be aware of these risks in order to make informed decisions about chosen volume settings for personal listening.
More research is needed, especially in children and teens, to better pool data and establish noise-auditory risk relationships using consistent age ranges, auditory impairment definitions, methodologies including tests sensitive to early noise damage, noise histories with years of exposure, and public health-based criterion, e.g. 70 dBA-NIHL risk, <20 dB Hearing Level threshold criteria for the normal hearing range on standard audiometry.
Safer Recreational Listening
Noisy venues often play loud amplified music or audio as part of the experience. Venues exceeding the non-occupational 70 dBA-NIHL limit include restaurants, wedding receptions, movies, including animated productions and musicals rated for children, bars and nightclubs, concerts, and sports events at arenas or stadiums, e.g. hockey, baseball, basketball, soccer,
football, NASCAR races.
Use of hearing protection is the exception and not the rule, despite the risks from even occasional or short exposures. Safer listening approaches depend on the venue and the age of the exposed person, including
avoiding noisy venues, turning down the volume if possible, and/or using well-fitting hearing protection devices such as earmuffs or earplugs.
It’s useful if individuals have options ready when needed, including high fidelity choices for clearer music and speech perception in recreational situations, e.g. pre-molded or custom-molded musician’s type earplugs (Mayes,2020). Hearing healthcare providers could have samples of different styles/features available for
educational purposes.
More Noise Prevention Needed
Noise prevention often falls outside the scope of individual actions or safer listening behaviours. This includes legislation and regulations specifying enforceable noise exposure standards for the public, including noise-sensitive populations.
Noise reduction actions might include mandatory noise emission limits, unified PAS manufacturing standards requiring safer engineered acoustic output limits, and warning labels or signs to inform the public about the hearing risks of loud products or venues, where hearing protection is recommended, offered, or required.
The American Public Health Association (2021) identifies that non-occupational noise in addition to recreational sound exposures must also be addressed, including transportation. Common sources of environmental noise pollution include home appliances, power tools or equipment, and public transit systems (Fink & Mayes, 2021).
Tordrup et al. (2022) estimate noise prevention programs and universal school-aged and adult hearing screening for early identification and intervention could result in economic and healthcare benefits or savings of up to $15 for every $1 invested. Universal coverage of hearing
protection devices was not considered.
Public hearing preservation and noise reduction programs
are unlikely to succeed without federal oversight, allocated funding, action plans, and stakeholder support (Shapiro, 1992).
Preventing noise is better for society and less expensive than the long-term healthcare and socioeconomic costs of hearing damage. Regardless of cause, hearing impairments are linked to lifelong negative impacts on cognition, speech communication, language development, mental health, music appreciation, sound localization, socialization, education, vocational success, and length of lifespan, including higher risk of dementia (Pienkowski, 2021, Stevenson et al, 2021; WHO, 2020).
Noise-induced cases could be avoided. It’s never too early or too late to protect hearing for life from harmful noise doses.
References
- American Public Health Association. (2021). Noise as a public health hazard. https://apha.org/Policies- and-Advocacy/Public-Health-Policy-Statements/Policy-Database/2022/01/07/Noise-as-a-Public-Health-Hazard
- Breinbauer, H., Anabalon, J.L., Gutierrez, D. & Carcamo, R. (2012). Output capabilities of personal music players and assessment of preferred listening levels of test subjects: Outlining recommendations for preventing music-induced hearing loss. The Laryngoscope, 122(11). https://doi.org/10.1002/lary.23596
- Eggermont, J.J. (2013). Noise and the brain: Experience dependent developmental and adult plasticity. Academic Press. https://www.elsevier.com/books/noise-and-the-brain/eggermont/978-0-12-415994-5
- Fink, D. & Mayes, J. (2021). Too loud! Non-occupational noise exposure causes hearing loss. Proceedings of Meetings on Acoustics. 43, 040002. https://doi.org/10.1121/2.0001436
- Mayes, J. (Winter 2020). Building a Hearing Protection Toolkit, Tinnitus Today, 45(3), 46-47. https://issuu.com/tinnitustoday/docs/tinnitustoday-winter2020-06-email?fr=sNjI1YzEyMDMzMg
- Mayes, J. & Fink, D. (2021). Unsafe at any sound: Hearing loss and tinnitus in personal audio system users. Proceedings of Meetings on Acoustics. 43, 040003. https://doi.org/10.1121/2.0001452
- National Institute for Occupational Safety and Health. (1998). Criteria for a Recommended Standard: Occupational Noise Exposure. Cincinnati, OH. https://www.cdc.gov/niosh/docs/98-126/pdfs/98-126.pdf
- Pienkowski, M. (2021). Loud music and leisure noise is a common cause of chronic hearing loss, tinnitus, and hyperacusis. International Journal of Environmental Research and Public Health, 18(8): 4236. https://pubmed.ncbi.nlm.nih.gov/33923580/
- SCENIHR (2008). European Commission—Scientific committee on emerging and newly identified health risks. Potential health risks of exposure to noise from personal music players and mobile phones including a music playing function. http://ec.europa.eu/health/ph_risk/committees/04_scenihr/docs/scenihr_o_018.pdf
- Shapiro, S.A. (1992). Lessons from a public policy failure: EPA and noise abatement. Ecology Law Quarterly, 19(1), 1-62. https://lawcat.berkeley.edu/record/1114290?ln=en
- Statistics Canada (2021). Table: 17-10-0005-01. Population estimates on July 1st, by age. https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=1710000501
- Speech-Language & Audiology Canada. (2019). Noise-Induced Hearing Loss Brochure. https://www.sac-oac.ca/professional-resources/resource-library/noise-induced-hearing-loss-brochure
- Stevenson, J.S., Clifton, L., Kuzma, E. & Littlejohns, T.J. (2021). Speech-in-noise hearing impairment is associated with an increased risk of incident dementia in 82,039 UK Biobank participants. Alzheimer’s & Dementia. https://pubmed.ncbi.nlm.nih.gov/34288382/
- Swierniak, W., Gos, E., Skarzynski, P.H., Czajka, N. & Skarzynski, H. (2020). Personal music players use and other noise hazards among children 11 to 12 years old. Int J. Environ Res Public Health, 17(18): https://pubmed.ncbi.nlm.nih.gov/32971992
- Tordrup, D., Smith, R., Kamenov, K., Bertram, M., Green, N., Chadra, S. & WHO HEAR Group. (2022). Global return on investment and cost-effectiveness of WHO’s HEAR interventions for hearing loss: a modelling study. The Lancet. 10(1), e52-e62. https://doi.org/10.1016/S2214-109X(21)00447-2
- World Health Organization. (2018). Environmental noise guidelines for the European region. WHO Regional Office for Europe. https://www.euro.who.int/en/publications/abstract/environmental-noise-guidelines-for-the-european-region-2018
- World Health Organization. (2020). World Report on Hearing. License CC-By-NC-SA 2.0 IGO. https://www.who.int/publications/i/item/world-report-on-hearing