Zoning is a traditional form of noise control. Its use, legend has it, goes back to the days of the ancient Sybarites, who some 2,500 years ago were intelligent enough to exclude blacksmithing, cabinetmaking, and other noisy industries from the residential city.
Zoning ordinances are used today primarily to protect residential areas from noises made within factories and commercial installations. Decibel limits are set on the amount of noise that can be radiated from within the factory to its boundary.
In Czechoslovakia, factories that produce noise exceeding 100 decibels must have a protective belt of 500 meters, and the external noise level at the point nearest any residential area must not exceed 50 decibels by day or 40 decibels at night. In the Soviet Union, plants with equipment causing a noise level over 90 decibels must be located on the leeward side of the nearest residential area and separated from it by an acoustic buffer zone, landscaped and planted with trees. Beyond this zone the noise must not exceed a specified level.
In Germany, certain industries have to receive a permit before being able to build or operate a plant, and this permit will only be granted if all technical advances are harnessed in the interest of noise abatement. Should an installation not abide with this regulation, the permit may be withdrawn.
The zoning concept can be expanded to offer protection from many undesirable noises. Coral Gables, Florida, applies zoning to noises made within the home, especially to residential air conditioning systems, to protect neighbors from each other and give them freedom from unnecessary noise. Unnecessary is interpreted to mean capable of being muffled, or designed to make less noise. By placing air conditioner noise control in a zoning ordinance instead of the typical anti-noise ordinance, Coral Gables avoided the impasse of having to establish a case for health damage.
(In reviewing some of the few statutory limitations on air conditioning, I asked a consulting engineer if society wasn't being too harsh on the industry, since there were no universal standards. He replied, "They don't need special standards to make an air conditioner that permits room conversation without straining my voice.")
Dallas, Texas, offers an example of how a public health department can utilize a zoning ordinance. In that city, the health department regulations use the noise standards incorporated in the Dallas Zoning Ordinance. The Village of Port Washington, on Long Island, used its zoning code to prohibit a company from using part of its industrial-zoned property for a private helicopter site. Where there is a commitment, there is a way.