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Evaluating the maximum playback sound levels from portable digital audio players
Stephen E Keith1, David S Michaud, Vincent Chiu
1Consumer and Clinical Radiation Protection Bureau, Health Canada, 775 Brookfield Road, Ottawa, Ontario, K1A 1C1 Canada. skeith@hc-sc.gc.ca
The Journal of the Acoustical Society of America
|June 10, 2008
Summary
Modern digital audio players can expose young Canadians to unsafe sound levels, potentially reaching 125 dBA. Earphone type and fit significantly impact listener exposure, highlighting risks associated with earbuds.
Area of Science:
- Audiology
- Public Health
- Consumer Product Safety
Background:
- Young people frequently use digital audio players.
- Concerns exist regarding maximum sound exposure levels from personal audio devices.
Purpose of the Study:
- To measure maximum sound output from modern digital audio players and earphones.
- To estimate potential listener sound levels and influencing factors.
Main Methods:
- Measured nine digital audio players and 20 earphones following European standard BS EN 50332.
- Investigated factors influencing listener sound levels, including earphone seal and player output.
- Explored simpler field measurement techniques.
Main Results:
- Playback levels ranged from 101 to 107 dBA at maximum volume.
- Estimated listener sound levels varied widely from 79 to 125 dBA.
- Intra-concha earbuds posed a higher risk due to earphone seal.
Conclusions:
- Digital audio players pose a risk of high sound exposure for young people in Canada.
- Earphone type and fit are critical determinants of listener sound levels.
- Simple field measurement methods can provide useful estimates of sound exposure.
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