Noise-induced hearing loss is a condition that is far too prevalent in today's society. And the sad truth is that noise-induced hearing loss is one hundred percent preventable. Although we are daily exposed to different noises from sources such as talking, television, and traffic, we usually hear these noises at safe levels that do not affect hearing. However, harmful noise, either from one instance or over a long period of time, can cause irreversible damage to a person's hearing, and it is important that people take the proper preventative steps in order to help prevent hearing loss.

Approximately fifteen percent of Americans between the ages of 20 and 69 are affected by noise-induced hearing loss. That's a total of about 26 million people in the United States alone, and this statistic is higher in comparison to the rate of noise-induced hearing loss in other countries, probably because of popular noisy recreational activities and work environments.

Noise-induced hearing loss can be caused in one of two ways. NIHL can occur when a person is exposed to a one-time impulse sound, such as an explosion. NIHL can also occur when a person is exposed to loud noises over an extended period of time. This persistent exposure to harmful noises has been most recently discussed in the news concerning people who listen to music on their headphones too loudly. But continual exposure to harmful noises has been a problem for years, especially for those who work in noisy working environments, such as shipping, woodworking, construction, manufacturing facilities, and other factories. NIHL can also be caused by loud noises produced by guns, lawnmowers, leaf blowers, shop tools, and, of course, music. Unfortunately, people usually do not detect their hearing loss until it is too late. Thus, people who are continually exposed to loud-noise environments should take preventative measures to ensure that their hearing stays safe.

The first step to take to prevent NIHL is to identify potential harmful noises. A noise can damage your hearing if it is over eighty-five decibels. To provide a reference, the average noise produced by steady traffic is about eighty-file decibels, and so you should try to limit your exposure to noises any louder than that. Of course, sometimes it is impossible to completely stay away from loud noises, especially if your work environment is inherently noisy. If this is the case, there are a variety of preventative measures you can take to help protect your hearing.

First of all, you can soundproof an area by installing noise barriers that absorb sound energy, effectively muffling and reducing loud, harmful noises. Soundproofing is a type of passive method for controlling unwanted sound and incorporates insulation, silencers, damping treatments, and absorptive treatments. And soundproofing works best in reducing middle to high frequencies.

A person can also wear protective earphones in noisy environments to reduce noise. And the best headphones to use are those that incorporate active noise cancellation.

Active noise cancellation has been a hot topic in the acoustic world in recent years. Active noise cancellation is a trait of many products that helps reduce harmful noises (it is not limited to headphone applications), and active noise cancellation is arguably better than any other form of noise reduction because it not only reduces noise, it cancels the noise.

Active noise cancellation systems usually consist of one or more sensors, a controller, and one or more speakers/actuators. The sensors identify the specific harmful noise and send that information to the controller. The controller than processes the information and creates a counteracting signal that is sent to the speakers/actuators. The counteracting signal is a sound wave that has the same amplitude as the unwanted noise but with an inverted phase. As this new wave combines with the wave of the original noise, a process called interference occurs which effectively cancels out noise and produces a sound wave that is so faint, it may be inaudible to human ears.

Active noise cancellation methods can be used to reduce noises caused by heavy equipment, class 7 and 8 trucks, trains, automobiles, aircraft, pumping booths, ships, manufacturing equipment, HVAC equipment, medical devices, heating and ventilation ducts, and more.

Active noise cancellation methods are more effective than passive methods (such as soundproofing) for a variety of reasons. They are more effective at cancelling out low frequencies. For soundproofing methods to effectively reduce low-frequency noises, the insulating materials used have to be extremely thick and heavy, whereas active noise cancellation systems do not change size to adapt to different frequencies. Active noise cancellation methods are also lighter and less bulky, making them easier to incorporate and install. And they are also able to block noise selectively (meaning that it blocks only the unwanted noise, not all noise). And quality active noise cancellation methods are capable of reducing noise up to 85 percent.

Our ears are sensitive instruments that must be treated with care. By taking the right preventative measures, such as utilizing products that feature active noise cancellation, you can protect your, your workers', and your family's hearing and help prevent noise-induced hearing loss.