BS EN ISO 717-2:2020 pdf free.Acoustics一Rating of sound insulation in buildings and of building elements.Impact sound insulation.
BS EN ISO 717-2 This document a) defines single-number quantities for impact sound insulation in buildings and of floors, b) gives rules for determining these quantities from the results of measurements carried out in one-third-octave bands in accordance with ISO 10140-3 and ISO 16283-2, and in octave bands in accordance with that option in ISO 16283-2 for field measurements only, c) defines single-number quantities for the impact sound reduction of floor coverings and floating floors calculated from the results of measurements carried out in accordance with ISO 10140-3, and d) specifies a procedure for evaluating the weighted reduction in impact sound pressure level by floor coverings on lightweight floors. The single-number quantities in accordance with this document are intended for rating impact sound insulation and for simplifying the formulation of acoustical requirements in building codes. An additional single-number evaluation in steps of 0,1 dB is indicated where it is needed for the expression of uncertainty (except for spectrum adaptation terms). Numerical values of the single-number quantities are specified where required for calculations. The rating of measurements over an enlarged frequency range is given in Annex A. A method for obtaining single-number quantities for bare heavy floors according to their performance in combination with floor coverings is given in Annex B. Example calculations of single-number quantities are given in Annex C. The rating of measurements with a heavy and soft impact source (rubber ball) is given in Annex D.Therefore an adaptation term C1 is introduced to take this effect into account, given as a separate number which cannot be confused with the value for Ln,w. This term is so defined that for massive floors with effective coverings its value is about zero, while for timber joist floors with dominating low frequency peaks it will be slightly positive. For concrete floors without cover or with less effective covering, it will range from -15 dB to 0 dB. BS EN ISO 717-2 pdf download.