With concerns raised and studies forged in recent years on health and learning problems experienced by children exposed to loud noise, it should come as no surprise that teachers are falling victim to noise induced hearing loss, caused by long hours spent in high decibel classrooms and gymnasiums.
However, it does come as a surprise, at least to school district administrators in Canada who have been testing teachers yearly for hearing impairment. This year, officials say, is the first time they have noted a marked rise in hearing loss among teachers.
Winnipeg houses Canada’s largest school district (they call them divisions), and this is where the teachers with noted hearing loss first surfaced.
“It’s a warning sign to us that we need to do something,” Division Director Eugene Gerbasi recently told CBS News. “If we don’t do something, individuals could potentially lose their hearing,” Gerbasi said.
So why no uproar about the children exposed to the same conditions as the teachers? They’re not at risk because they do not log the long hours, year after year, in gyms, band classes, shop classes and other high decibel classrooms. In some schools where teachers were tested, the loudest classes include choir, music, band, and industrial arts. However, the gym appears to be the worst culprit across the board, with noise levels routinely measured above 90 decibels.
Under Manitoba's workplace legislation, noise levels cannot exceed 85 decibels.
The same problem affects teacher worldwide, and American teacher are expected to be exposed to similar noise overages as their Canadian peers, although many U.S. public schools no longer have the funds to support band, choir, and industrial art classes, and no evidence of routine hearing tests being performed on U.S. teachers could be found, American teachers who teach gym and band classes are reporting moderate to profound hearing loss over time, and many are candidates for cochlear implants.
However, prevention is the name of the game when it comes to noise pollution and protecting our hearing,
A study by researchers at the University of Toronto suggests that music teachers are routinely exposed to noise levels that could result in hearing loss. Gerbasi told CBS News that teachers and staff at the Winnipeg School Division will soon have to start wearing protective hearing devices.
Nick Dyck, a gym teacher for more than 20 years in the Winnipeg Division, says he has lost the ability to hear certain noise levels and participate readily in conversations because he has to strain to hear people. Dyck, now a physical education and health consultant for another Winnipeg school division, says he believes his hearing loss is related to the noise levels he experienced as a gym teacher for two decades.
Another study led by research associate Alberto Behar, and electrical and computer engineering professors Hans Kunov and Willy Wong, generate findings that exposure to general noise over the course of an eight hour day is marginally acceptable, elevated noise levels during teaching periods can cause damage to the inner ear.
"The hair cells of the inner ear simply crumble under the load, and they don't grow back again," Kunov explained.
The Ontario Occupational Health and Safety Act caps acceptable noise levels at 90 decibels – the equivalent of a power lawn mower – for more than eight hours in any 24 hour period. Noise levels on the job should not exceed 90 decibels -the equivalent of a power lawn mower-over eight hours of a 24-hour period.
In their study, Wong and his colleagues used noise dosimeters to measure noise exposure to 18 teachers from 15 Toronto high schools, and found that peak noise levels exceeded 85 dB for 78 per cent of the teachers. In an average eight-hour day exposed to these decibel levels, their findings stated that 39 per cent of the teachers in the study faced potentially harmful noise levels, and acoustics are as much to blame as the noise itself.
“The world is louder than we think,” Wong exclaimed while reviewing their findings.
Most classrooms are constructed of concrete blocks and linoleum flooring, which produces a highly reflective sound surface. Wong said that schools should consider protective measures such as sound absorbing materials and carpet, and teachers might also want to wear protective earplugs and consider periodic hearing checks.