A 10-mintue exposure to 120 dB sound typically shifts your threshold of hearing
temporarily from 0 dB up to 28 dB. Studies have shown that, on average, 10 years
of exposure of 92 dB sound causes a permanent shift of up to 28 dB.
What intensities correspond to 28 dB and 92 dB
To understand the intensities that correspond to 28 dB and 92 dB, we need to first understand the decibel scale and how it relates to sound intensity.
The decibel (dB) scale is a logarithmic scale used to measure sound levels. It is based on a ratio between the sound pressure level and a reference level. The reference level usually used is the threshold of hearing, which is around 0 dB.
Now, let's calculate the intensities corresponding to 28 dB and 92 dB.
To calculate the intensity corresponding to a certain sound level, we can use the formula:
I = I₀ * 10^(L/10)
Where:
- I is the sound intensity in watts per square meter (W/m²).
- I₀ is the reference intensity, which is typically set at 10^(-12) W/m².
- L is the sound level in decibels.
For 28 dB:
I = I₀ * 10^(28/10)
Substituting I₀ = 10^(-12) W/m²:
I = 10^(-12) * 10^(28/10)
Simplifying the equation:
I = 10^(16/10) W/m²
Calculating the value:
I ≈ 39.81 W/m²
So, the sound intensity corresponding to 28 dB is approximately 39.81 W/m².
For 92 dB:
I = I₀ * 10^(92/10)
Substituting I₀ = 10^(-12) W/m²:
I = 10^(-12) * 10^(92/10)
Simplifying the equation:
I = 10^(46/10) W/m²
Calculating the value:
I ≈ 2511.89 W/m²
Therefore, the sound intensity corresponding to 92 dB is approximately 2511.89 W/m².