How is noise typically measured?

Noise is measured in decibels, which is a logarithmic unit used to express the ratio of a particular sound's intensity to a reference intensity. The decibel scale is useful in measuring sound because it reflects how humans perceive changes in loudness. Sound intensity can vary across a wide range, so using a logarithmic scale compresses this range into a more manageable format. A difference of 10 decibels represents a tenfold increase in sound intensity, making it convenient for comparing noise levels.

Other measurement units mentioned, such as hertz, volts, and pascals, serve different purposes. Hertz measures the frequency of sound waves, indicating how many cycles occur per second, which relates more to the pitch of a sound rather than its loudness. Volts are a unit of measurement for electrical potential and are not directly related to sound. Pascals measure pressure, including sound pressure, but they do not express the perceived loudness in the way that the decibel scale does. Thus, decibels are the most appropriate and commonly used unit for assessing noise levels.