Noise Pollution

Individuals can take many simple steps to protect themselves from the harmful effects of noise pollution. If people must be around loud sounds, they can protect their ears with ear plugs or ear protectors. They can muffle sound by using acoustic ceiling tiles, draperies, carpets, and sound-absorbing furniture in their homes, offices, and schools. They can also buy quieter models of machines and let store owners and manufacturers know that they prefer quieter products. Individuals can also help their communities investigate noise pollution and develop regulations to reduce the problem locally.

Some communities have enacted anti-noise ordinances. New York City issues fines to people who run excessively noisy air conditioners, to street construction crews whose equipment is too loud, and to impatient drivers who honk their horns. Police in Redondo Beach, California, can remove large speakers from cars if the music can be heard more than 50 ft (15.2 m) away. In 1999, a judge in Fort Lupton, Colorado, began sentencing teenagers convicted of playing their stereos at high volumes to time spent listening to court-selected vocal artists.

Communities can also reduce noise by locating freeways far from residential neighborhoods, by reducing the speed on freeways and other high-speed roads, by requiring developers to plant trees and shrubbery as sound mufflers, and by requiring people to build houses and other structures with materials that help absorb sound.

Many engineers are aware of the need to reduce noise pollution, and some of them are busy devising new ways to solve the noise problem. In Japan, Yokohama Tire Company has introduced a new high-performance tire that gives a quieter ride. Korean engineers have developed an anti-noise system for computers that reduces a typical noise level of 30 decibels to a nearly undetectable 20. United States researchers have invented a new composite consisting of alternating layers of sound-absorbing foam and sound-containing vinyl that can be placed in machinery housings to reduce noise. At the Georgia Institute of Technology, an inventor has developed a "quiet curtain" for nursing home patients who cannot sleep that is made of noise-absorbing materials that can reduce noise by 12 decibels. In Germany, roads are paved with materials that reduce sound, tires are manufactured to whine less, and lawn mowers and other equipment are designed to operate quietly. Manufacturers in some Australian states must label the noise level of products such as chain saws and lawn mowers.

As the human population continues to increase, the amount of noise in our world will also grow as we crowd together with gadgets, machines, and vehicles. To help ease the impact of this increasing amount of noise, some companies are developing a new technology called anti-noise. Anti-noise works by emitting a sound that exactly matches the noise. When the sound waves from the anti-noise device meet the sound waves from the noise, they cancel each other out. In such a case, no sound waves reach our ears; we do not hear the noise. Anti-noise can work as a kind of muffler on a noisy engine, or it can be built into headphones to silence all approaching noise. Even if we cannot eliminate noise pollution, we may be able to use anti-noise devices to escape some of the damage that noise can cause.