Noise as Perceived by the Community *

Different composite noise indexes are compared and CNR or NEF is believed best suited for judging community annoyance and physiological effects. Noise levels in areas close to airports are very high and in some communities may constitute a hazard for hearing loss. Effects of intense noise on other physiological reactions are less well known, but should be studied. Interference with communications and sleep are the most serious effects of aircraft noise exposure, with sleep interruption rated relatively more annoying. Increasing noise accounts for about 25% of the total variance in human annoyance; attitudes, experiences and other human factors are even more important. Responses from persons with only moderate fear of crashes and feelings that authorities are somewhat misfeasant in minimizing noise, indicate that about one-third have “high annoyance” at NEF 20-25, and almost half at NEF 30+. Measures for noise abatement are briefly described, including a time schedule for reducing maximum noise levels, modifying existing engines, introducing new “quiet” engines producing 10 EPNdB less noise than the existing FAA rule, reducing the number of flights by rationalizing duplicating flights to optimize capacity of airplanes, and development and enforcement of compatible land use zoning regulations.