Proper training, protection help prevent hearing loss Published March 1, 2007 By Master Sgt. Brad Sprague 35th Fighter Wing public affairs MISAWA AIR BASE, Japan -- Many times, hearing loss is due to personal choices such as firing a weapon without wearing proper hearing protection, listening to loud music or riding motorcycles. According to the Center for Disease Control and Prevention, normal hearing requires that all parts of the auditory pathway are working correctly. This pathway includes the external ear, middle ear, inner ear, auditory nerve, and the connection between the auditory nerve and the brain. The exact location and nature of the problem in the auditory pathway determines the type and severity of a person's hearing loss. "We sometimes see what's called 'Significant Threshold Shift,' and they are pretty common," said Lt. Col. Kevin Connolly, commander of the 35th Aerospace Medicine Squadron. "But in order to be considered a true hearing loss, you need a 'Permanent Threshold Shift." Significant Threshold Shift is an average change of +/- 10 or more decibels at 2,000, 3,000, and 4,000 hertz in either ear without age corrections. Permanent hearing loss, also known as Permanent Threshold Shift, progresses constantly as noise exposure continues month after month and year after year. "We do not have that many cases of hearing loss," said Colonel Connolly. "So we do not see that many people with PTS, and there are no trends on base in all the shops we look at to indicate there are problem areas with hearing protection." According to the colonel, people who work on the flightline, pilots, people who work with loud machinery or loud construction tools are strictly monitored. "Certain shops are monitored more closely," said the colonel. "We test noise levels in all the Air Force shops we monitor. If testing reveals the noise is too high, the people working in those shops get put on the hearing protection program. "Anyone who works around noise above a certain decibel level gets a yearly hearing test and gets re-educated about proper hearing protection," Colonel Connolly said. "When they come in for their occupational exam they are asked questions about any symptoms that might indicate hearing loss. If they answer yes to any of those questions they see their provider and then we do an evaluation and examination in addition to the hearing test. Every now and then we will get a PTS on somebody which requires further evaluation by audiology and/or ear, nose and throat doctors to take a look to make sure no other problems exist." The colonel said most shops are doing a very good job at using dual hearing protection and "using the hearing protection devices that we recommend," he said. To help prevent hearing loss, he said people should wear hearing protection devices as taught and trained by public health personnel, and by their supervisor. "Also, wear dual hearing protection and ensure personnel use the devices we recommend because there are some hearing protection devices out there that are less than optimal," said the colonel. Some people may have the misconception that living on an Air Force installation contributes to hearing loss. Not true, according to the colonel. "Living on base does not contribute to hearing loss," explained Colonel Connelly. "Being in your home or out shopping when an aircraft takes off at times may seem loud, but it will not cause hearing loss. There are many places on base that are not on the hearing protection program because they are not exposed to excessive noise levels." Colonel Connolly said anyone wishing to find out more about hearing loss should contact public health or bioenvironmental engineering if they have any questions.