FAA Turns Down the Volume.

According to the 1998 annual report of the Air Transport Association, U.S. airlines flew 423.3 billion passenger miles in 1987, a number that grew to 619.5 billion miles in 1998. According to the Federal Aviation Administration (FAA), air traffic is expected to double nationally by the year 2017. Increased air traffic also means an increase in airplane noise. To help regulate the impact of noise on the environment, the FAA established the Airport Noise and Capacity Act in 1990, which required all civil jet aircraft over 75,000 pounds to reduce noise and lessen their environmental effects overall by 1 January 2000.

According to the FAA's 1998 progress report to Congress on the transition to quieter airplanes, aircraft have fully met these requirements. "This report demonstrates that we are moving forward in the reduction of aircraft noise in the nation's skies, and that the U.S. airline industry will continue with efforts to reduce noise and improve environmental impacts," says Secretary Rodney Slater of the Department of Transportation.

The Airport Noise and Capacity Act requires that older, so-called stage 2 aircraft meet the noise standards applied to the quieter stage 3 aircraft being built today, which incorporate the latest technology for suppressing jet-engine noise. Usually stage 3 aircraft are 10 decibels quieter than stage 2 aircraft. An increase of 3 decibels is equivalent to a doubling of the sound energy.

Despite the quieter standards, an increase in air traffic operations concerns people such as Anne Kohut, publisher of the Airport Noise Report, a biweekly newsletter. Kohut believes it's hard to tell exactly what effects noise pollution has on health because of the paucity of studies performed. The studies that have been performed do provide some indication, however, of the impact noise pollution may have on health.

Research published in volume 10 (1993) of Children's Environments by Gary Evans, a professor of design and environmental analysis at Cornell University, and Stephen J. Lepore, an associate professor of psychology at Carnegie Mellon University, suggests that living or attending school near a major noise source can lead to elevated blood pressure in children. Research published in the September 1997 issue of Environment and Behavior by Evans found that children chronically exposed to aircraft noise have poorer reading skills than children attending elementary school in a quieter setting.

In 1998, psychologists from Cornell conducted research with a group of German third and fourth graders exposed to noise from Munich International Airport. They discovered health problems such as higher blood pressure and boosted levels of stress hormones. The study, published in the January 1998 issue of Psychological Science, suggests that noise increases psychophysiological stress among children. "This study is probably the most definitive proof that noise causes stress and is harmful to humans," said Evans in a press release from Cornell.

In November 1998, a conference titled Noise Effects '98 was held in Sydney, Australia. Organized by the International Commission on Biological Effects of Noise, it was the seventh international conference concerning noise as a public health problem. The conference looked at noise's effects in nine areas, including its effects on sleep and its influence on performance and behavior, and evaluated the research that has been done thus far within these specific areas. Findings from the congress suggest that new standards for measuring noise's effects need to be refined so that the public can be made more aware of their relative strengths and weaknesses.