Hearing Conservation & the Effects of Noise
Today we live in a world that is louder than ever before, where environmental noise seeps into nearly every facet of life. From common home appliances to exhilarating events, we operate in situations where dangerous levels of sound are an everyday fact of life.
Just because noise permeates our life doesn’t mean that increasing sound levels are harmless. Far from it, in fact. While many factors can contribute to hearing loss, the vast majority of permanent hearing loss is noise-related hearing loss, largely caused by gradual hearing damage done over the course of a lifetime.
Noise and Your Hearing
Your hearing involves an incredible relationship between the sensory mechanisms in your ear and the processing power of your brain. Our hearing relies heavily on an arrangement of tiny and delicate cells in the inner ear called “hair cells”. Hair cells are attuned to pick up sound waves in the air, picking up the vibration and sending an electric signal to the brain where it is interpreted.
We are born with roughly 15,000 hair cells in each ear to pick up fine nuances in sound. Unfortunately, most of us move through life with far less. Hair cells are dynamic, but they are also fragile. Loud noises can stress them to their breaking point, damaging the cells with the strength and pressure of the sound wave. Some loud noises cause permanent damage to hearing after hours of exposure, while very loud noises can damage the hair cells instantly.
Hair cells do not regenerate – like neurons, the hair cells we are born with are the hair cells we carry through life. These sensitive cells also can’t repair damage that occurs to them. When a loud sound takes a hair cell out of commission, it never regains functioning leaving a permanent gap in how we hear. As we age, our hearing carries the impact of everything we’ve heard. Gradual damage to our hearing can accumulate into permanent hearing loss.
What Is Dangerous Noise?
Our ear’s hair cells have evolved to be sensitive to a wide range of noise. The quietest sound perceivable by the human ear is 0 decibels. Our hearing can detect sounds without the risk of damage up to around 75 dB, about the sound of highway traffic. Sounds above 75 dB contain the potential to damage our hearing. The louder the sound, the quicker lasting injury is done.
People who work in loud environments should be especially aware of their noise exposure. At a sound level of 85 dB, roughly the volume of a factory floor, hearing damage can occur after 8 hours. Exposure times drop dramatically the louder the noise. Just 10 decibels higher, 95 dB, is only safe for an hour of exposure. When sound levels reach 105 dB, about the sound of a live rock concert or sports event, unprotected hearing sustains damage in under 10 minutes. Our hearing is instantly damaged if it is exposed to sounds as loud as 115dB, such as gunshots or fireworks. Exposure to sounds above 120 dB will also cause physical pain in the ear.
Keeping your hearing healthy requires that you to be aware of your “noise diet” and take measures to protect yourself. Musicians, hunters, factory workers and machinists should all use custom noise protection to keep their hearing safe. Regardless of your profession or hobbies, you can monitor your noise exposure with a simple decibel meter app for your smartphone or digital device. Programs like Decibel X can be used to discreetly monitor the noise in your surroundings. If you are frequently around hazardous noise levels, you need to protect your hearing and should strongly consider custom hearing protection.
Staying away from noise-related hearing loss also means it’s important to get an annual hearing exam. A hearing exam can detect issues with your hearing early, and can help you curb your noise exposure. When hearing loss is detected and treated early, it is easier to adapt to treatment and prevent further hearing harm. Noise-related hearing loss is cumulative, so failing to protect and monitor your hearing just causes it to worsen.