Acoustics

MP3 Player Listening Sound Pressure Levels among 10 to 17 year old Students

Exposure to loud noise on a consistent basis can adversely affect one’s hearing. Health Canada is working to reduce the incidence of noise-induced hearing loss in Canada. In this study, Health Canada examined childrens’ exposure to noise from portable digital audio players. Estimates were made of daily exposure to sound from portable digital audio players. Subjects were students (93 males, 126 females) in the age range of 10 to 17 years. The exposures were estimated for each subject using a measurement of typical sound levels (i.e. headphones were placed on a mannequin with realistic rubber ears; measurements were detected by microphones placed where the eardrums would normally be) and the average daily duration of use. Based on these estimates 3.2% of subjects exceeded the common occupational noise exposure level limit in Canada of 85 A-weighted decibels (dBA) for 8 hours per day. When the subjects set their audio players to the maximum volume that they would use, it was estimated that the daily exposure for 77.6% of the students would be below the level for which there is no known risk of permanent hearing loss, 75 dBA for 8 hours per day. The results of this research can be used to assess whether new measures are needed to manage the potential risk from listening to MP3 players. Research results are published in the Journal of the Acoustical Society of America, 2011 Nov;130(5):2756-64.