MEASURING SOUND

STC stands for Sound Transmission Class. This is a method of gauging sound transmission loss through a wall. The American Standards and Testing Materials criteria is universally accepted by architects, designers, manufacturers, contractors and distributors of acoustical building products. The original acceptability of STC 34 walls must be reconsidered with the advent of increasing noise pollution.

STC Assessment:

Poor: 30 - 39
Good: 40 - 49
Better: 50 - 59
Excellent: 60 - 69

While an STC rating is given in terms of points, the data is given in terms of decibels. A decibel, or dB, is a unit measure reflecting "how loud" a sound is. A sound pressure level of 0 dB represents the threshold of hearing in the most sensitive frequency range of a young, healthy ear, while the thresholds of tickling or painful sensations in the ear occur at about 120 to 130 dB.

Noise pollution:

In general, noise pollution refers to any noise irritating to one's ear which comes from an external source.