By Mickey Scullard
Meeker County Public Health
Hearing loss is a common health problem experienced by farmers.
In our earlier farming health project, we tested farm families' hearing. The results were astounding!
After the results were tallied, the testing showed that seven out of 10 men had a hearing loss, with almost two-thirds of those having hearing loss in the moderate to severe range.
Four out of 10 women had a hearing loss. One-third of the women with hearing loss had moderate to severe loss. More than 50 percent of the men aged 30-39 had hearing loss. Seventy-two percent of the farmers never used hearing protection.
This occurred because noise causes hearing loss by over-stimulating the thousands of hair cells in the inner ear. The hair cells change sound waves to nerve impulses. When the hair cells are damaged by excessive noise exposure, they do not heal and they no longer transmit sounds to the brain.
Noise-induced hearing loss is painless, gradual and cannot be fixed. It happens little by little and cannot be felt. By the time most people notice that they can't hear very well, nothing can be done to restore hearing to its original condition.
Hearing loss occurs at a level much lower than most people think. The rule of thumb is if you have to speak in a really loud voice in order to be heard - then the sound is too loud.
We can measure how loud sound is with a unit of measurement called decibels (dB). We can use normal conversation as a "measuring stick." Normal conversation is measured at 60 dB. However, the decibel level of the noise isn't the only factor we need to look at when determining the harm the noise may due to one's hearing.
It is also important to know how long one can be around a noise before it begins to cause damage to the ear.
For example, many types of workers are protected from hearing loss in the worksite by OSHA regulations. If noise levels exceed 85 dB for over eight hours in an industrial worksite, employees are required to wear hearing protection. The key point however, is that the louder the noise, the less time it takes to have hearing loss.
When the farming health nurse went to the farm and measured the decibels of different machinery, she found many at 85 dB or higher.
A tractor idling was 85 dB; a tractor at 80 percent load was 100 dB. This means that the maximum time a farmer could operate his or her running tractor without a cab and without hearing protection is two hours.
A chopper or compressor runs 90 dB; a full throttle combine runs 110 dB. At these levels, the maximum amount of time a farmer can operate this without hearing protection is a half-hour. An old chainsaw runs at 120 dB, and squealing sows and power tools are each about 100 dB.
Interestingly, most farmers tested had hearing loss in their left ear. This was caused by farmers looking over their right shoulder to watch their implement, which meant that their left ear was closer to the loud engine.
Noise-induced hearing loss is nearly 100 percent preventable by simply wearing hearing protection. Farmers who already have hearing loss can prevent further loss by wearing hearing protection.
Starting today, you should wear ear plugs or ear muffs around loud noise, especially around the machinery mentioned above.
The old adage "Out of sight, out of mind" holds true for hearing protection. Farmers need to have ear protection in visible places so they remember to wear it.
One strategy is to have baggies with ear plugs hanging in the machinery shed, in the repair shop by the tools, next to the chainsaw, and in the tractor. You can purchase ear plugs in many hardware stores.
And finally, you don't get used to loud noise; you lose your ability to hear it. Make using hearing protection a habit.
If you have questions or would like additional information,
call your local public health agency: McLeod County Public Health, coordinator,
Becky Felling at 320-864-3185; Meeker County Public Health. director, Ann
Bajari at 320-693-5370; and Sibley County Public Health, director, Mavis
Pautz at 507-237-2962.