The recently adopted Illinois Noise Pollution Control Regulations will control noises emitted from “property-line-noise-sources,” e.g., industrial facilities, business, and commercial establishments, etc. The comprehensive regulations contain two parts: the first part contains a “nuisance” provision, and the second part contains octave-band sound pressure level limits for property-line noise sources. For purposes of these regulations, land is classified into three categories according to use, which correspond to industrial, commercial, and residential uses. The numerical limits, which will apply to a given facility, are dependent upon the land usage of both the noise emitter and noise receiver. Impulsive sounds are regulated by A -weighted sound levels, while “prominent discreet tones” are regulated in terms of 1/3-octave-band sound pressure levels. More stringent nighttime limits will apply to new facilities which emit sounds to residential lands. Compliance times for existing noise sources range from one to three years, while new facilities must comply immediately. These regulations are the first step in a program designed to reduce noise pollution in Illinois-future regulations will control noises emitted from transportation sources and construction sources.