To define your specific problem, you need a basic understanding of how to quantify both your unwanted noise and the sound level that will be acceptable. The difference between those two values is the degree of sound control you need to achieve with your door opening. That understanding requires a brief overview of the science of sound and its measurement.

We begin with a few important definitions:

• Sound pressure levels are measured in decibels—or dB. The scale of measurement used to simulate sound across the audible frequency range is denoted as dBA. Figure 1 illustrates the impact of dramatic changes in dB levels.  It is also important to note that the human ear perceives changes in loudness caused by even small changes in those levels. Each 10 dB increase doubles the sound reception—and the annoyance or discomfort that goes with it.

To go from definitions to practical applications, we first need to understand how sound is transmitted from its source through a barrier.  Next we will explain how a barrier is rated for its ability to inhibit or block sound. That gives us the ability to compare different barriers. With that information, we can examine the role of gasketing systems in optimizing the performance of doors that function as sound barriers.