07 Jan How Loud Is Loud?
How Loud Is Loud?
Most of us take our sense of hearing for granted-we assume that we hear what everyone else hears. Loss of hearing may not be realized until a friend or spouse screams in frustration, “Why don’t you ever listen to me!!” This is because hearing loss is usually gradual. Normally, it doesn’t hurt, so we don’t know it’s happening. It doesn’t annoy us like losing our eyesight. In fact, it is sometimes a blessing to tune out all the clatter and noise of the city and workplace.
Yet our ability to hear when we want to is precious and must be protected. Employers often reduce the amount of noise in the workplace by enclosing or muffling loud machinery, but they usually can’t eliminate it entirely. Employers may also rotate workers out of an area so they needn’t experience a full work day of excessive noise exposure. Whatever the length of time you work in an area with high noise levels, you are probably required to wear a type of hearing protection. Some people consider this a nuisance. The more you know about those ears of yours, however, the more likely you will take responsibility for protecting them.
Do you realize that noise exposure off the job can also damage your hearing? The critical sound level when hearing protection should be worn is 85 decibels (dBA), established for an 8-hour time weighted average. The louder and longer your exposure, whether at work, at home, or during recreation, the more likely your hearing will be damaged. If you want to have a sense of “how loud is loud,” the following examples, along with their decibel rating, will give you an idea:
| 20 | a faint whisper |
| 30-40 | quiet pleasant sounds, a bird chirping |
| 40-50 | quiet to normal office sounds |
| 50-60 | normal conversation |
| 70-90 | heavy machinery, electric motors, garbage disposal, city traffic |
| 100-120 | jack hammer, power saw, motorcycle, lawn mower, rock music |
| 140+ | nearly jet engine, gun shot (this level causes pain) |
Wear your hearing protection!
Many disposable or reusable plugs are available and most of these reduce noise by about 20-30 decibels. The noise reduction rating (NRR) is usually marked on the package, or on the box if they come in bulk. However, since the NRR is established in a laboratory with perfectly fitted plugs, experts recommend that the true rating is generally about 7 decibels less than indicated. Hearing protectors of the ear muff type are usually closer to the actual NRR.
Some degree of hearing loss is part of the normal aging process, but young people should also be warned about the dangers of a rock concert, boom box, lawn mower or loud car engine. Of course they may not listen to you, but if they have permanent hearing loss they won’t be able to listen to anyone, will they?
Hearing Protection – Use it!