Hunyadi Z.

The gas-turbine reconstruction of a particular thermal power station took place in an industrial area extending among living spaces. A part of the living spaces suffered from a significant noise charge during the time the former obsolete apparatus was operating. However, the noise protection design – in order to abolish the former complaints – only focussed on the noise protection of the living space that had already been under the charge of industrial noise. The new turbine, the steam-boiler and the connecting apparatus were installed to a building considerably further. The noise protection design of the terminal constructions and chimney shut down with an adequate result, but focussed on exclusively the territories charged before. In addition, the sizing only concentrated on examining and noise control of the apparatus emitting permanently. Although the temporarily operating equipment were also supplied with noise control constructions, after the commission of the power station, new residential complaints were drown up. According to the residential complaints, the monitoring measurements ordered by the operator detected that the temporarily operating equipment overran the noise limit at those territories, which are on the other side of the power station and had not been not suffering from noise charge. It turned out, that the period time of the temporarily operating equipment was significantly undercounted, and it totally filled – moreover exceeded – the estimation time of the night period, and become a determinate noise source. Besides, the noise sources emitting a high amount of steam in a short time caused such a noise phenomenon – really disturbing , according to subjective opinions – which has a significant and negative influence on noise spread, and made the evaluation of enquiries more difficult.