Dave Harton didn't realize that the music he loves can be a threat to his hearing.
The 15-year-old Ellicott City resident learned that the unfortunate way this month at a rock concert in Baltimore. The noise left him with hearing loss and tinnitus - a constant ringing in the ears.
He experienced what doctors say is an often-overlooked health hazard: high-decibel noise, an increasing problem for people of all ages.
Harton considers himself lucky. His hearing damage registers on tests but isn't very noticeable.
The ringing, while irritating, is audible only in silence and could go away.
But the experience spurred his mother, Marcia Harton, into a one-woman information campaign.
She wanted to know why she never knew of the danger, and why few checks are made on the musicians who put on loud concerts.
"I've learned a lot - painfully," she said.
More than 20 million people in the United States are exposed to noise levels that could damage their hearing, according to the American Speech-Language-Hearing Association in Rockville.
Determined to keep others from accidentally putting their ears in harm's way, Harton has called doctors, rock musicians, concert organizers, the state Department of Health and Mental Hygiene, hearing-loss groups and others who could offer advice.
Part of her mission is to get health teachers in Howard County schools to warn students about the danger of noise, an idea supported by Linda Rangos, the school system's instructional facilitator for health education.
"This is so important to me," Harton said.
John Schaefer, an environmental health officer for the Johns Hopkins University and hospital, said society is getting noisier but many people aren't aware of the risks.
The hazards of smoking and drug use are much better publicized, he said.
"People do not think about noise - because you cannot see it - as a hazard," he said. "The noise creeps up on you."
Occupational Safety and Health Administration standards state that a person can be safely exposed to 90-decibel sounds - such as power lawnmowers - for eight hours.
The time limit drops to one hour for noises at 105 decibels and 15 minutes for noises at 115 decibels.
"Concerts have been said to be as loud as 110 to 120 decibels," Schaefer said.
Dave said he had never heard anything about noise hazards.
Before the concert this month, he hadn't noticed problems listening to rock music.
He had gone to several concerts, and he plays electric guitar in a five-member band, Splinter Of Life.
At the two-hour concert Sept. 9 at the Inner Harbor, he had what he thought were great seats - up front near the speakers.
"It was, like, really loud," he said. "It got to where my ears started hurting a little."
When the music stopped, "My ears were ringing. Everything was kind of muted. I couldn't hear my own voice. It was kind of scary at first," Dave said.
His hearing improved the next morning, but tests later in the week showed hearing loss.
It's unclear whether the loss will be permanent.
"I'm pretty glad it's not worse, but sometimes the ringing is really annoying," said Dave, a freshman at Centennial High School. "The other day, I was trying to take a test, and it was hard to concentrate."
Dave will be outfitted with something extra the next time he attends a concert, plays his guitar or does anything that's expected to be loud.
"We're having some musicians' earplugs made," said his mother.