Acoustic Fencing and Noise Mapping
New technology has allowed the development of a type of computer modelling called Noise Mapping. It consists of a series of microphones placed around the track and outside the perimeter to monitor noise levels, and how they vary, throughout a race. The microphones are all linked through a computer server to sophisticated software that creates a colour coded map of the track and the surrounding area to highlight the hot spots and regions that suffer the most from noise pollution. The data is also collected over time, which can make a considerable difference to the expected results. A person standing at various points of the track throughout a practice session or a race might draw conclusions as to where acoustic fencing would be most appropriate, but because the map is built up over time the results can be quite enlightening. Areas that may have been thought the most problematic, such as the start line or the area around the Grandstand, may actually show up as being only short term noise pollution points. Other areas away at the back of the track that may have features, such as tight bends followed by long straights, that lead cars and bikes to change gears and rev hard. So while spectators and track staff may not be aware of the noise pollution, local residents may be all too aware of irritating noise levels.
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