You would probably use the buttons as part of a campaign to prevent the expansion of an airport further, to prove that aircraft noise is already louder than the

You would probably use the buttons as part of a campaign to prevent the expansion of an airport further, to prove that aircraft noise is already louder than the authorities say it is. I doubt the current measurement of aircraft noise at ground level over wide areas and long periods is that great, and airport operators have a heavy incentive to understate the levels of noise pollution.