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“Bill, that’s not true. Earbuds don’t keep the outside noise out. You turn them up louder to block out the noise around you.” “Well, I wasn’t wearing them that long.” William started to get defensive. Zeke opened his science book to the chapter on sound. “Look at this. This chart shows the decibel levels of different sounds. Loudness is measured in decibels. According to this, a whisper is between 15 and 20 decibels. Normal conversation, like we are having now, is around 40 or 50 decibels.” William leaned in to get a better look. “Yeah. And a rock concert is around 120 decibels. But I’m not at a rock concert. I am listening to my own music through headphones.” Zeke looked at him. “But I could hear it when you came in. In fact, I knew that you were coming before I saw you. What is your volume set on?” William checked the dial. “Uh, it’s at six.” “I read the other day that if earbuds, the kind that go inside your ear, are set at higher than five for more than fifteen minutes, then it can lead to hearing loss.” William was not convinced. “How can that damage my ear? I don’t get it.” Zeke found a diagram of the ear in his textbook. “Here is your ear. Right here in the inner ear are tiny hairs. These are actually nerve endings that send impulses to your brain. These tiny hair cells can be damaged by loud noises. In fact, it is pretty easy to damage them. A damaged hair cell means that the messages will not get to your brain. Which means you will suffer hearing loss or hearing damage.” “Okay, smarty. What is too loud?” “Actually,” Zeke continued, “it’s not just about volume. It’s also a question of how far away you are from the source of the sound. In your case, with those earbuds in, you can’t get much closer. You have to be concerned about how long you are exposed to the loud music, and how often.” William looked a little worried. “And with our band, I guess we are exposed to loud music more than a lot of people.” “Yeah. And, it has to do with

your family, too. If your parents or grandparents have a history of hearing loss, then you might be more susceptible to it.” “I had no idea.” Zeke gathered his books and put them in his backpack. “Certain jobs or hobbies are

decibel a unit used to compare the loud- ness of sounds, using the symbol dB impulses electrical signals that travel along nerves in the body Words to Understand

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