olume is the main contributor to NIHL. It’s generally safe to listen to noises up to 75 dB, but anything louder can begin to cause hearing loss. As the volume of the sound increases, the amount of safe listening time decreases, so although it’s safe to listen to 75 dB sounds for hours, it’s only safe to listen to a 90 dB sound for a few minutes. iPods have come under fire for featuring top volumes of up to 115 dB (the equivalent of standing next to a pneumatic drill), which can cause damage in as little as five minutes per day. Teenagers have been found to be particularly at risk, and a study at Children’s Hospital in Boston found that even though many teens kept their device’s volume at the maximum, they were unaware of just how loud the music was. Many teenagers also trust that all the manufacturer’s default volume settings are safe for their ears.

Dial It Down—Way Down

In 2006, a class-action lawsuit alleged that Apple had failed to properly warn its customers about the dangers of using its product at high volumes. Apple does warn about excessive volume in iPod manuals, and includes a feature that allows parents to set volume limits on their children’s devices. Some speculate that in order to prevent further ear injuries, the next generation of iPods will feature a lower maximum volume, and perhaps even a sensor that could calculate how long a person has been listening at what volume, and could automatically shut off. These new devices could then remain off for a specific amount of time, giving the user’s hearing a chance to recover and stabilize. Apple has already capped volume at 100 dB for iPods sold in Europe.

Some companies have introduced earphones that automatically reduce noise output to safer levels, so that no matter how loud a music device is set, the volume will never exceed 85 dB. Although it’s a promising development, critics of products like the iHear Safe headphones charge that they create a false sense of security while doing nothing to address the problem of increased listening time, which is just as serious of a risk factor as volume. The best recommendation for iPod lovers who want to save their senses is to upgrade to headphones that block out ambient noise, because people naturally turn down the volume when they don’t have to compete with outside sounds. Another idea is to use a set that fits over the entire ear area, as opposed to the earbud style that sits directly in the ear canal.

The best suggestion, however, is to simply give your ears an occasional break. Letting your hearing recover after exposure to loud noises can help it return to normal, as can wearing earplugs at concerts or in other noisy situations. Your ears will thank you, and they’ll do so with a whisper, not a shout.

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