Accept sound advice

By Helen Murphy (NURSE MURF)

DO your ears ring? Do they feel full? Do you have trouble understanding conversations, especially higher-pitched women and children? How well are you hearing on the phone? Does anyone complain you speak too loud or the volume of your TV or radio approaches that of a rock concert?

If you’re nodding, chances are you’ve got noise-induced hearing loss. You’re not alone. Farmers tend to have more hearing problems than other professions. Why? It’s the machinery and no one insisting on wearing ear protection.

How do we hear?

We hear by a chain reaction. Noise is funneled into our ears as sound wave vibrations. They hit the ear drum which moves three tiny bones in our inner ear. That movement vibrates a small window in the cochlea, which is a fluidfilled, hair-lined structure that looks like a nautilus shell. The fluid moves the 40,000 hairlike hearing cells, which convert the movement into nerve impulses. These are sent directly to the brain and are interpreted as sound.

When your ears are hit by a lot of noise (vibrations measured in decibels) all day long or as a sudden blast, the hearing cells are damaged. Getting away from the noise can give these cells a chance to regenerate. But if your ears are continuously exposed to noise day after day, the cells have no chance to recover and they die. At this point, you will have permanent hearing loss. It is like a lawn. If you walk on it a bit, the grass will spring back. But if trampled continuously, it will die.

Hearing loss is preventable

Hearing damage comes from a combination of noise intensity and duration: too loud for too long.

What is too loud? Anything over 85 decibels. If you have to shout to be heard over noise, if the noise hurts your ears, if you feel a bit deaf for a few hours after being around loud noise, this is over 85, leading to damage.

The rule of thumb is if you can’t hear someone three feet away from you, it’s too loud. Do you know how loud your kids MP3 player at full volume is? How about your machinery? See the chart below.

How long is too long? It depends on the noise intensity. For instance, without hearing protection, it takes about a minute to damage your ears using a skill saw at 112 decibels and 15 minutes on a tractor without a cab.

The good news is that noise-induced hearing loss is preventable. And if you already have some hearing loss, you can reduce its progression. How? Use formable or premolded earplugs, canal caps, or ear muffs every time you are exposed to loud noises.

If you don’t want your kids to have the hearing of a 50 year old by age 25, make them do the same. Also keep them away from noise in the fi rst place. Don’t try cotton. It does not work because the sound goes right through. Keep your cab doors closed. This will improve the benefi ts of a cab on noise reduction by 50%.

Did you know that hearing protection will help you hear your equipment and other’s voices better? It is because background noise is blocked out. Also, protective earmuffs come with built-in radios so you can listen to music, news or sports safely while working.

Remember, once you lose your hearing, it is permanent. So save the ears you have! Another bonus of noise reduction is that it reduces accidents, stress, anxiety and fatigue at the end of the day.

Murphy, outreach and education director at the University of Washington Pacific Northwest Agricultural Health and Safety Center, may be reached by phone at 206-616-5906 or by e-mail at

Bar graph showing intensity of sound in decibels vs. the many different sources of sound, and the safety limit of 85 decibels

Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More