Half my married life has been spent saying "What?" from another room in my home. My wife swears it's selective hearing, but an audiologist attributes my hearing loss in part to my passion for woodworking. And, as tough as it is to admit, much of it could have been prevented.
Most noise in normal life won't cause ill effects. Normal conversation, for example, has a sound level of approximately 60 decibels (dB); driving a car, about 70 dB. But stepping into your shop changes everything. Most power tools run well over the 85-dB threshold that will result in hearing impairment with prolonged exposure. And the additional sound from the actual cutting or routing of wood only makes it worse. (See the chart below.)
Fortunately, a simple solution exists: hearing protection. I have experimented with a variety of products and (finally) faithfully use them.
Hearing protectors are rated by their ability to reduce noise, expressed as a noise reduction rating (NRR). If a tool generates 100 dB and the hearing protector has a 30-dB NRR, then the effective noise level reaching your ear is 70 dB—well within the safe range. (Technically, there is a bit more math involved, but these values are pretty standard and provide an easy way to judge the effectiveness of a hearing protection device.)
Let's hear it for your options!
The first and least expensive protection comes from foam earplugs [photo below]. Simply compress the foam by rolling it between your finger and thumb, and then insert the plug into the ear canal. As the plugs expand to their original shape, they typically provide a noise reduction rating of 32. Once they look really dirty or become a bit hard, they should be discarded.
An aural band (NRR 23 typical) [photo below]uses the spring-fit of the band to keep the earplugs in place and are easily removed, replaced, and retained, as needed. If your ears are a bit sensitive, the constant pressure imposed by the band may make them uncomfortable.
Ear muffs (NRR 30 typical) [photo below] fit over the ears. Some styles include a built-in radio, as well as Bluetooth capability. NRR values vary depending on the design. Padded muffs can be very comfortable, unless your ears are bigger than the muffs. The two drawbacks I've found are wearing them over safety glasses, which can compromise the fit and effectiveness of both; and they can be a bit warm in the summer with prolonged use.
A relative newcomer is the earbud-style protector [photo below], with an NRR of 27 and Bluetooth connectivity. These not only reduce noise levels but also allow you to listen to music streamed from a smartphone or tablet. (Wisely, they won't let you run the music louder than 85 dB.) I like that they insert as easily as earplugs and eliminate the fit and sweat issues of the ear-muff style.
So, listen up: If you don't use one of those four options in your shop now, you may find yourself needing a more expensive option you get to wear all the time [photo below]. I'll be happy to discuss this with you more. You'll just have to speak up.