Easy Thinking

October 22, 2009

How Loud is Your iPod?

Filed under: Information — remadd @ 7:34 am

In a study of 31 college students, about half listen to music on portable music players, like iPods, at levels that can, over longer periods of time, cause permanent hearing loss, say researchers from the University of Southern Mississippi. A teenager can have his own personal concert, as loud and as long as he likes. Parents might wonder if the volume levels their teen is listening to could cause hearing damage. It is possible, according to this new study of college aged students.

The study sample was small and the lab setting was not necessarily reflective of choices people would make in real life, so more research would be needed to confirm the findings. Even so, the results add to a growing body of research that indicates the potential hazards of these prolific devices.

For years, scientists have known that volumes over 85 decibels (dB), about the sound of a hair dryer, can cause significant hearing loss if people listen in for many hours over many years.

The United States Department of Labor’s Occupational Safety & Health Administration (OSHA) has set standards for how long employees can listen to certain sounds, depending on intensity. For instance, people should only listen to 100 dB for two hours, and 115 dB for 15 minutes or less, according to OSHA. On the decibel scale, an increase of 10, say, from 100 to 110, means that a sound is 10 times more intense.

The University of Southern Mississippi researchers say the problem is two fold, as iPods not only can reach hazardous volumes of around 130 dBs, but their personal nature makes it almost impossible for authority figures to determine if someone is listening at levels that could damage hearing.

In the past, someone walking around with a boom box or radio, you can hear how much loudness they are generating, and if you are an authority figure like a parent or a teacher or a supervisor, you can tell them, that’s too loud, said lead researcher.

To determine the volume levels these college teens were listening to, researchers studied students who had owned personal music players for no more than three years. The students listened to Summer of 69 by Bryan Adams at their preferred sound level as the researchers measured the intensity at exactly the same spot in the song.

The majority of the teens, 55 percent, listened at very loud levels, or more than 85 dB. About 26 percent listened at levels between 70 dB and 85 dB, and 19 percent preferred volumes less than 70 dB.

The college students tend to want to set volume levels that are pretty high. And if they continue to listen at levels above 85 dB for many years, it can gradually cause significant and permanent hearing loss.

Another concern, teenagers today can listen to their iPods for up to 20 hours without recharging them, an audiologist and doctoral candidate at the University of Colorado at Boulder, said.

Though no significant hearing loss was detected in the teens in the study, researchers believe that the participants may not have owned personal music players long enough to experience damage.

People who have had music players for longer periods of time in our future study, that have now had them for five or six years, could produce completely different data.

iPods are becoming more popular by young children. So subjects that are younger will have a longer amount of years that they have been listening to these devices and could cause further damage.

Researchers would like to see more action taken to make listeners of portable music players more aware of the risks to their hearing. Manufacturers could test their devices and mark volume settings with the decibel level. This allows the person themselves to monitor, and then someone else, a teacher or a parent, could look at the device and see the volume control setting.

If you feel your personal listening habits have caused possible damage to your hearing and you live in Arizona, Purtone Hearing Centers which provides Arizona audiology and hearing aids can provide you with important answers to help you make smart decisions about healthy hearing.




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