Noise pollution is not a necessary price to pay for living in an industrial society. Much can be done to reduce the severity of the problem. For example, vehicles and other machines can be built to produce less noise. Four-cycle engines can replace much noisier two-cycle engines in such products as lawnmowers, motorboats, and jet skis. Labels that indicate the noise levels of appliances and tools can help consumers avoid noisy products and choose quieter alternatives.
Even after noise is generated, steps can be taken to reduce human exposure to it. At homes or in offices, insulation of walls and double-glazing of windows can muffle sound from traffic, neighbors, and other sources from the outside world. Sound walls along highways can shield nearby neighborhoods from traffic noise. Individuals should protect themselves with earplugs or mufflike ear protectors, particularly when noise levels exceed 85 decibels.
In the industrialized nations, governments have laws and policies to counter noise pollution. In the United States, at least six federal agencies are involved in controlling noise pollution. Since 1969 the FAA has monitored and controlled noise from airplanes. The agency requires that new aircraft meet specified noise standards and that old ones be retrofitted or retired. Local airport authorities, with FAA approval, reduce the impacts of noise pollution by routing flights over water or unpopulated areas on takeoff and landing, and by limiting traffic at night. The FAA also encourages airports and local governments to take steps on the ground, such as constructing sound barriers, insulating buildings, and restricting residential development in noisy areas. In extreme cases, airports have relocated people living under flight paths.
The Occupational Safety and Health Administration (OSHA) is charged with reducing noise in workplaces. Under OSHA regulations, no exposure above 115 decibels is permitted, exposure up to 115 decibels is