Noise is a major source of violations of the comfort of staff of the enterprise, located directly next to the operating compressor equipment. Therefore, often accounting noise characteristics needed in the design, selection and installation of compressor stations. What are the sources of noise? The cause of the noise is the sound waves produced by compression and expansion in air and other media. For example, the speed of sound in air is about 330 m / sec. The main parameter of evaluation of noise is its frequency. It corresponds to the number of vibrations of sound waves per unit time, and as a unit frequency measurement is used hertz (Hz). 1 hertz (Hz) is equal to 1 vibration sound waves in 1 second.
Direct measurement of the strength of noise is a rather complicated technical problem. In addition, more problem is a significant difference (thousands of times) in place of noise, for example, in a quiet conversation, and take-off aircraft. Therefore, for wide use in technical calculations have entered a special logarithmic value – decibels (dB), which allowed to present the most used noise performance in comparable and convenient to compare values. Table 1 shows the magnitude of noise level, corresponding to different sources. Table 1. The magnitude of noise Noise level, dB About 160 aircraft during takeoff 100 Siren 90 (85-95) Rail, Tram 85 Music Center in 1980 playing the piano 75 68 Hoover Washing Machine 53 (50-55) Exhaust Fan 42 (40-43) Refrigerator 20 Rustle There are also pages of two other important parameter estimation noise: sound power level (noise) and sound pressure level.