A Survey of Noise Environments in Industry

Abstract

A survey has been made of steady-state noise in various manufacturing industries. Pressure levels in octave bands and corresponding loudness values are classified according to type of industry. Measurements are further sub-divided into “machine levels” taken close to the principal noise sources, and “area levels” taken at greater distances where a larger number of workers is affected. In the noisiest industries about 50 percent of the machine levels were between 95 and 115 db with a loudness between 50 and 500 sones. The area levels in some of the quiet industries were between 77 and 81 db with a loudness around eight to ten sones. A correlation between over-all level and total loudness indicated a range of about 9 db for noises of different character having the same total loudness. The noise spectra of several typical machines will be presented also. Median, quartile, and extreme values are used to specify the range of values encountered.