The balanced approach for controlling airport noise is basically about first exhausting all other possibilities for reducing noise nuisance to communities near flight paths. Only then can airport-by-airport rules be adopted banning the noisiest of the International Civil Aviation Organisation-defined Chapter 3 aircraft.
And then, when an airport is allowed to ban some aircraft, affected types can only be those within a 5dB margin of the upper limit set by Chapter 3.
The three tenets of the balanced approach are:"land use planning" in the airport's vicinity should be applied; variation of operational procedures or runways to reduce the number of people affected by flight- path noise must have been adopted; minor variations of aircraft operational techniques may be tried, like reducing allowable payload, or the aircraft flap setting for noisy types so that their actual noise and emissions fall below the 5dB margin.
Source: Flight International