Noise-induced hearing loss (NIHL) is on the rise again. After declining somewhat toward the end of the 20th century, new generations of Americans are experiencing NIHL. While about 10% of millennials have hearing loss due to noise exposure, the members of Gen-Z have it at a rate of 17%. This is especially concerning when we consider that Gen-Z is the younger of the two generations.
About Noise-Induced Hearing Loss (NIHL)
Any sounds above 85 dBA (decibels A-weighted) can cause hearing loss after about 8 hours of exposure. This is the metric that the Occupational Safety and Health Administration (OSHA) uses to protect workers from NIHL in hazardous sonic environments. If a worker’s job exposes them to 85 dBA or higher throughout their shift, the employer must take several steps to protect the worker’s hearing. 85 dBA is about the noise level we experience mowing the lawn with a gas-powered mower.
For every additional 3 dBA of noise, the safe period of exposure is cut in half. That means by the time sound reaches 100 dBA, only about 15 minutes of exposure can cause permanent hearing loss. 100 dBA is about the noise level we experience while riding a motorcycle, or at the average high school dance. At 130 dBA, hearing loss happens nearly instantaneously. We can experience this level of sound by standing on the tarmac during a jet’s takeoff. Gunfire tends to be even louder than this, reaching 140–175 dBA.
One way that we can lessen the impact that a sound has on our hearing is to move further away from it. This may not always be possible depending on the situation, but for every doubling of our distance from a sound source, the effective decibel level drops by 6 dBA. In other words, there’s a big difference between mowing the lawn and hearing your neighbor, two houses down, mow their lawn.
Measuring Sound to Stay Safe
If you’re unsure of whether you’re being exposed to unsafe sound levels in a given situation—or on a regular basis—you should take a measurement of the environmental sound at your listening position (where your ears are in the space).
You can download an SPL (sound pressure level) meter app for your smartphone. While these tend to be more accurate on iOS devices, where the microphone sensitivity is standardized, they may be less accurate on Android devices unless you calibrate them. Calibration requires the use of a separate SPL meter that is known to be accurate.
A dedicated SPL meter can be purchased for around $20. These should be even more accurate than apps run on iOS devices, but can also be used to calibrate apps for general use when you don’t have your dedicated SPL meter with you.
Use Earplugs
There are several types of earplugs, but they are all successful at doing the most important thing: protecting your ears! Remember to ensure that your earplugs are rated to attenuate (reduce) the sound by the appropriate amount. This is represented as NRR, or “noise reduction rating.” Earplugs even with an NRR of 33 (highest available for typical earplugs) will not be appropriate for shooting firearms, where the decibel levels reach 175 dBA. That would still expose you to an ear-splitting 142 dBA! (Firearms enthusiasts should wear both earplugs and earmuffs, or purchase custom hearing protection designed for firearms use.)
Disposable Earplugs
These cost around $1.00 or less per pair, and are intended for one-time use. They are typically manufactured out of foam and tend to have a low NRR. While they are certainly effective at blocking out sound, they tend to upset the balance of the frequency spectrum, attenuating high frequencies more than low ones. This can create an unnatural sound and make music-listening less enjoyable. Some may also find them uncomfortable or ineffective, depending on the individual’s ear canal shape.
Reusable OTC Earplugs
Reusable earplugs come in a variety of shapes and sizes, typically using a flexible silicone tip. They may cost between $15–30. They attenuate more sound than disposables, in many cases (though note that this is not always desirable). While they typically attenuate frequencies more evenly between low and high, they still do not reach the sound quality offered by custom hearing protection.
Custom Hearing Protection
Custom-molded earplugs require that we take an impression of your ear canal. This is sent to a lab where an earplug is manufactured that fits your ear canal perfectly. We’ll talk with you about the activities for which you intend to use your earplugs, and ensure you receive the appropriate amount of attenuation. Custom hearing protection can also be a more cost-effective way than disposable earplugs for employers to provide hearing protection to employees, as they can be used daily for years.
