Measurement of Noise

Sound level meter measures sound level pressure (intensity of sound) at one point and at given moment and evaluates quantitatively any noise of industrial, environmental, and aircraft origin. The procedure of estimation of sound level requires a number of measurements at different times during the workday. A typical sound level meter consists of a microphone that is connected to a voltmeter calibrated in decibels. Noise analyzers make it possible to estimate noise signal at each frequency simultaneously. The results are demonstrated at the display as dependence of sound intensity level on the frequency. Vector sound intensity is the net rate of sound energy. The measurement of this parameter is useful for determination of noise source power, measurement of a moving sound source, and for location of noise sources.