85 dBA and you are exposed to it for at least 8 hours.Sound is more likely to damage your hearing if it is: As dBA rises, your hearing is more likely to be damaged, and more quickly than you might expect. For instance, the lowest note on a tuba (16Hz) will have a much lower dBA reading than a dB reading.Įven small increases in dBA level can have a big impact on your hearing health. However, a lower frequency sound that isn’t processed as effectively through the ear will have a lower output level. For instance, the high-pitched E string on a violin has very similar dB and dBA levels. In the frequencies that our ears respond to best, measurements for dBA are just as high as they are in dB. When sounds contain frequencies are too high or too low for us to hear -as in ultrasonic and infrasonic sounds -our cochlea doesn’t respond at all. It doesn’t respond as well to frequencies that are much higher or lower. (Read more about how we hear or watch a video on how sound travels to the brain.) The cochlea responds best to frequencies in the range of human speech. The cochlea can respond to a certain range of frequencies, or pitches of sound. The cochlea is a snail-shaped organ inside your inner ear that allows you to hear. Because of this, dBA gives us a better idea of when sound can damage your hearing. While the dB scale is based only on sound intensity, the dBA scale is based on intensity and on how the human ear responds. A-weighted decibels, or “dBA,” are often used when describing sound level recommendations for healthy listening. Sometimes we use different versions of decibels. Using the logarithmic decibel scale, if a sound is 80 decibels, and we add another 10 decibels, the sound will be ten times more intense, and will seem about twice as loud to our ears. If we build up another 10 feet, the building will be 12.5 percent taller, which would seem just slightly taller to us this is a linear measurement. To understand this, think of a building that is 80 feet tall. This kind of scale better represents how changes in sound intensity actually feel to our ears. While many standard measuring devices, such as rulers, are linear, the decibel scale is logarithmic. A modern version of it is still used today to diagnose hearing loss.ĭecibels are different from other familiar scales of measurement. An audiometer is a device that measures how well a person can hear certain sounds.

Decibels (dB) are named in honor of Alexander Graham Bell, the inventor of both the telephone and the audiometer. We measure sound intensity (also referred to as sound power or sound pressure) in units called decibels. Another important and easily measured factor is sound intensity, or volume. Has a noisy situation ever left you grimacing and clutching your ears? Why do some sounds seem so loud? Many factors influence how loud a sound seems, including how long it lasts, the sound’s frequencies (or pitches), and the environment in which you hear the sound.

Why are decibel scales useful