(…) The Huron Heights Grade 9 student attended an assembly about hearing loss, organized by a dozen Grade 11 students, their health teacher and the Hearing Foundation of Canada. She was one of two volunteers who had the volumes of their iPods tested.

When Klooster went to the front of the large cafeteria packed with students and was asked to turn her iPod to her normal listening volume, it was easily audible across the room.

When Gael Hannan of the Hearing Foundation tested it, she found it was at 120 decibels — louder than a typical rock concert and a level at which it’s impossible to listen to even briefly without risking hearing damage.

“I didn’t know it was going to be the loudest she had ever recorded,” Klooster said later. “It was a bit shocking.”

Hannan explained exposure to loud noises damages hairs in the cochlea, a part of the inner ear, which transmits sounds to the brain.

Ringing in the ears that goes away is a form of temporary hearing loss, and a warning sign ears have been exposed to a dangerous level of noise.

When Hannan asked the students who had ever had ringing in their ears, almost all put up their hands.

Dangerous noise levels have to do not only with the sound volume but also the length of time you’re exposed to it. A dial tone or a vacuum cleaner is 85 decibels — safe for eight hours. But with every three decibels a sound goes up in volume — a difference difficult for people to detect — safe exposure time is cut in half.

So the noise of a forklift, at 88 decibels, is safe for four hours; a subway, at 91 decibels, for two hours. A typical school dance or snowmobile is 100 decibels, which is safe without hearing protection for only 15 minutes. A leaf blower, at 110 decibels, is safe for about a minute and a half.

There is evidence many teens have already suffered hearing loss.

A recent B.C. study of 140,000 young people entering the workforce found 22 per cent had the early warning signs. A further 4.6 per cent had worse hearing.

Some lose hearing for reasons such as ear infections in early childhood, but only 12 per cent of children starting school have hearing loss, suggesting noise causes most of the increase, Hannan said.

Caroline Cook, 16, took the stage to tell students what it’s like to be hard of hearing. The Toronto student was born with 90 per cent hearing loss. She explained she has to be facing people to understand what they’re saying. She often has to ask friends to repeat themselves, and they often brush her off with a “never mind.”

Often, Cook doesn’t hear people say Hi, and people assume she’s stuck up. She never has private phone conversations because she has to use a speaker phone. She can only watch TV or go to movies when closed-captioning is available, which limits her selection.

Her hearing dog alerts her to noises such as the toaster popping or her mother calling. Still, “I face a lot of challenges in my life,” Cook said.

Jordan Smith, 18, who plays in a band with Huron Heights students Brendan White, 17, and Riley Moore, 15, was also born with hearing loss, though less severe than Cook’s.

He and his band all wore earplugs as they played at the assembly, but Smith has no choice. He has tubes in his ears that contain microchips to augment his hearing. He said amplifiers cause so much reverberation for him, he gets an instant migraine.

Musicians who wear earplugs actually hear the music better because there’s no distortion from too-loud sounds, White said.

After the assembly, when Klooster turned her iPod on, she turned it down. “It meant a lot to me to figure out how loud I’m listening to my music,” she said. “I pretty much listen to it full blast, so I guess I need to work on that a little bit.”

Source: Waterloo Record, Canada
http://news.therecord.com/News/Local/article/332468