Contrary to popular beliefs and media reports, the hearing of young people in the United States does not appear to be worse than that of the prior generation. Recent large-scale studies of youth entering the workforce indicate that average hearing levels are the same as, or better than, those of young people 20Р30 years ago (Harrison, 2008; Hoffman et al., 2006; Rabinowitz et al., 2006). Similarly, controlled epidemiologic studies of school-aged children show that average hearing levels among 6- to 19-year-olds in the 1990s were the same or better than children evaluated two decades earlier (Holmes et al., 2004).
Although there are many potential culprits for ear and hearing difficulties, surveys have found that young people routinely experience a great variety of noise sources, many potentially hazardous (Danhauer et al., 2009; Neitzel & Meinke, 2006; Rabinowitz et al., 2006; Smith et al., 2000). Individual susceptibility to noise is paramount—but not quantifiable—with the current state of the art. Other key factors that influence hearing risk include the level of the sound and the duration and frequency of exposure (how loud, how long, and how often).
Risk criteria for damage are based on the concept of increased risk with increased dose, a function of the how loud and how long part of the equation. According to the 1998 risk criteria suggested by the National Institute of Occupational Safety and Health (NIOSH), which are commonly used to calculate hearing risk due to both occupational and recreational noise, a "risky" noise exposure is considered to be an average sound level of 85 dBA for an eight-hour duration. Using NIOSH's 3‑dB doubling rate for estimating equivalent risk, an eight-hour exposure to average sound levels of 85 dBA is considered to be roughly comparable to 88 dBA for four hours, 91 dBA for two hours, 94 dBA for one hour, and so on.
Recent research evaluating typical listening levels and usage time suggest that few young people are at substantial risk of hearing loss from PMP listening (Airo et al., 1996; Portnuff et al., 2009; Williams, 2005). A greater risk is posed by recreational activities with higher average sound levels, such as hunting/target shooting; using power tools; operating motorized vehicles such as motorcycles, snowmobiles, and ATVs; and attending noisy sporting events and concerts. Gunfire, in particular, is considered to be the most onerous noise hazard, posing high risk of permanent hearing loss and even the possibility of instantaneous hearing damage. Figure 1 [PDF, 1.1MB] summarizes typical sound level ranges for several common sources of recreational noise.
Although the range of sound levels varies, average levels are much lower for music listening (either via home stereo speakers or PMPs with earphones) than for many other sources of leisure noise. As an example, using NIOSH's 3‑dB doubling rule for estimating risk, a music listener would need to be exposed to typical PMP sound levels for 16 hours (average sound level of 76 dBA) to equate to a 15-minute exposure to power tools (average sound level of 94 dBA).
An additional aspect of assessing hazardousness of PMP and leisure noise is that the most common source of substantial hearing risk is noisy occupations in which individuals are often exposed to louder sounds, for longer hours, and more often than they are to recreational noise. Recent studies of young construction workers, for example, indicate that the majority of these individuals' total noise exposure is a consequence of occupational, not recreational, sources (Neitzel et al., 2004).
Ahmed, S., King, M, Morrish, T.W., Zaszewska, E., and Pichora-Fuller, K. (2006). "A survey of the use of portable audio devices by university students," Canadian Acoust., 34(3), 64–65.
Airo, E., Pekkarinen, J., & Olkinuora, P. (1996). "Listening to music with earphones: an assessment of noise exposure," Acustica 82, 885–894.
Bradley, Fortnum and Coles. (1987). "Research note: Patterns of exposure of schoolchildren to amplified music," British Journal of Audiology, 21, 119–125.
Danhauer, J.L. et al. (2009). "Survey of college students on iPod use and hearing health," Journal of the American Academy of Audiology, 20(1), 5–27.
EN. (2000). "Sound system equipment: Headphones and earphones associated with portable audio equipment, maximum sound pressure level measurement methodology and limit considerations, Part 1: General method for "one package equipment," European Comm. for Electrotechnical Standardization EN50332-1, Brussels.
Felchlin, I., Hohman, B.W., & Matefi, L. (1998). "Personal cassette players: a hazard to hearing?" in Advances in Noise Research, Volume 2, Protection Against Noise, Ed. Deepak Prasher, Linda Luxon, and Ilmari Pyykko, Whurr Publishers, Ltd., London.
Fligor, B.J. (2007). "Portable digital music players and the potential risk for hearing loss," Update 19(1), 9–11.
Fligor, B.J., & Cox L. C. (2004). "Output levels of commercially available portable compact disc players and the potential risk to hearing," Ear and Hearing, 25(6), 513–527.
Fligor, B., & Ives, T. (2006). "Does earphone type affect risk for recreational noise-induced hearing loss?" presentation at Noise-induced Hearing Loss in Children Meeting, Cincinnati, Ohio.
Harrison, C. (2008). "Do young workers have worse hearing now?" presentation at annual conference of the National Hearing Conservation Association, Portland, OR.
Hoffman, H.J., Ko, C., Themann, C.L., & Franks, J.R. (2006). "Declining trends in noise-induced hearing loss (NIHL) in children based on U.S. Health Examination Survey," Presentation at Noise-Induced Hearing Loss in Children at Work and Play Conference, Cincinnati, OH.
Holmes, A., Niskar, A.S., Kieszak, S., Rubin, C., and Brody, D. (2004). "Mean and median hearing thresholds among children 6 to 19 years of age: the third National Health and Nutrition Examination Survey, 1988 to 1994, United States," Ear and Hearing, 25(4), 397–402.
IEC. (1985). "Sound system equipment, Part 1: General," Int. Electrotechnical Commission, IEC 268-1, Geneva.
ISO. (2002). "Acoustics- Determination of sound immission from sound sources placed close to the ear – Part 1: Technique using a microphone in a real ear (MIRE technique)," Int. Org. for Standardization, ISO 11904-1:2002, Switzerland.
ISO. (2004). "Acoustics- Determination of sound immission from sound sources placed close to the ear – Part 2: Technique using a manikin," Int. Org. for Standardization, ISO 11904-2:2004, Switzerland.
Katz, E.E., Gerstman, H.L. Sanderson, R.G. , & Buchanan, R. (1982). "Stereo earphones and hearing loss," New Eng. J. Med. 307(23), 1460–1461.
Keith, S.E., Bly, S.H.P., Chiu, V., and Hussey, R.G. (2001). "Sound levels from headphone / portable compact disc player systems III," Proceedings of Inter-Noise 2001, Ed. by R. Boone, Inst. of Noise Control Eng., Poughkeepsie, NY, paper 492.
Keith, S.E., Michaud, D.S., and Chiu, V. (2008). "Evaluating the maximum playback sound levels from portable digital audio players," J. Acoust. Am. 123(6), 4227–4237.
Martin, G.Y. and Martin H. W. (2007). The Jolene Cookbook, Oregon Health and Science Univ., Portland, OR, www.dangerousdecibels.org.
Neitzel, R. and Meinke, D. (2006). "Noise exposure among children and young adults: what do we know, and what do we need to find out?," Presentation at Noise-Induced Hearing Loss in Children at Work and Play Conference, Cincinnati, OH.
Neitzel, R., Seixas, N., Goldman, B. and Daniell, W. (2004). "Contributions of non-occupational activities to total noise exposure of construction workers," Ann. Occ. Hyg. 48(5), 463–473.
NIOSH. (1998). "Criteria for a recommended standard – occupational noise exposure, revised criteria," Natl. Inst. for Occup. Saf. and health, DHHS (NIOSH) Pub. No. 98-126, Cincinnati, OH.
Passchier-Vermer. (1999). "Pop music thru headphones and hearing loss," Noise Control Engineering Journal, 47(5), 182–186.
Portnuff, C. and Fligor, B. (2006). "Sound output levels of the iPod and other MP3 players: is there potential risk to hearing?" Presentation at Noise-Induced Hearing Loss in Children at Work and Play Conference, Cincinnati, OH.
Portnuff, C., Fligor, B. and Arehart, K. (2009). "Teenage use of portable listening devices: a hazard to hearing?" presentation at annual conference of the National Hearing Conservation Association, Atlanta, GA.
Rabinowitz, P.M., Slade, M.D., Galusha, D., Dixon-Ernst, C., Cullen, M.R. (2006). "Trends in the prevalence of hearing loss among young adults entering an industrial workforce 1985 to 2004," Ear Hear., 27(4):369–75.
Rice, C.G., Rossi, G., and Olina, M. (1987). "Damage risk from personal cassette players," British J. Audiol. 21, 279–288.
Smith, P. Davis, A., Ferguson, M. and Lutman, M. (2000). "The prevalence and type of social noise exposure in young adults in England," Noise & Health, 6, 4–56.
Torre III, P. (2008). "Young adults' use and output level settings of personal music systems," Ear & Hearing 29(5), 791–799.
Williams, W. (2005)."Noise exposure levels from personal stereo use," Int. J. Audiol. 44, 231–236.