Undersökning av ljudnivåer på skolgårdar
- samt hur fasad och fönster dimensioneras med uppmätta värden
AcousticsNoiseSoundSchoolSchool yardEquivalent sound levelMaximum sound levelSound reduction indexFacadeAkustikBullerLjudSkolorSkolgårdEkvivalent ljudnivåMaximal ljudnivåReduktionstalFasad
This report is written on commission by WSP Acoustics. The report studies the outdoor sound levels on school yards in Stockholm. The questions given by the company to be answered was what are the actual sound levels at diffrent school yards with low traffic noise and how can you construct a facade element that reduces the sound level from the outside and meet the indoor requirements. Mesurements for four hours was done at eight schools set north and south of the city centre. The measurement period included one school break and one lunch break. The results of the measurements were that the equivalent and maximum sound level had small variations between the schools with some exceptions.The equivalent sound level was Leq 58-62 dB(A) and this shows a small variation. The school with the highest equivalent sound level of 67 dB was Maria skolan. This high level can be explained by more children on the school yard together at the same time etc. The maximum sound level was 85-89 dB(A), this if the level for Sofia skolan 82 dB was ignored. The level 85-89 dB(A) also shows a small variation. Calculations of the sound reduction index (R'w) for facade elements were also carried out for all the schools. The resulting sound reduction index for the whole facade was 34-41 dB. After assuming a 200 mm thick concrete facade for Sjöstadsskolan another calculation of building elements gives that the window have to reduce R'w 32 dB to meet the indoor requirements. In the future WSP Acoustics will use this report to choose building elements such as windows when building or rebuilding schools. It can also be used if any of the eight schools in this report needs a window changed to improve the acoustics.