Acoustics - Intensity Level (Decibels) Formula

Introduction to Acoustics - Intensity Level (Decibels) Formula

The intensity level (IL) also known as sound pressure level (SPL) in decibels (dB) is a logarithmic measure of the sound intensity relative to a reference intensity. The formula used to calculate the intensity level is represented as IL = 10 log₁₀(I/I₀), where IL is the intensity level in decibels, I is the sound intensity, and I₀ is the reference intensity (usually set at a standard threshold of hearing). It is important to note that the intensity level is proportional to the logarithm of the sound intensity ratio. Therefore, a difference of 10 decibels corresponds to a tenfold difference in intensity. This formula is used in the field of acoustics to quantify and compare sound intensities and detect the potential for hearing damage in relation to prolonged exposure.

Parameter usage:

• I= sound intensity
• I₀= reference intensity

Output:

• IL= intensity level in decibels

Data validation

The parameters I and I₀ should be greater than zero.

Summary

This calculator takes into account the sound intensity and reference intensity and outputs the corresponding intensity level in decibels.