BS EN ISO 717‑1:2020 pdf download.Acoustics — Rating of sound insulation in buildings and of building elements Part 1: Airborne sound insulation
1 Scope This document a) defines single-number quantities for airborne sound insulation in buildings and of building elements such as walls, floors, doors, and windows, b) takes into consideration the different sound level spectra of various noise sources such as noise sources inside a building and traffic outside a building, and c) gives rules for determining these quantities from the results of measurements carried out in one‑ third‑octave or octave bands for example in accordance with ISO 10140‑2 and ISO 16283‑1. The single‑number quantities in accordance with this document are intended for rating airborne 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 for the expression of uncertainty (except for spectrum adaptation terms). The required numerical values of the single‑number quantities are specified according to varying needs. The single-number quantities are based on results of measurements in one‑third‑octave bands or octave bands. For laboratory measurements made in accordance with ISO 10140‑2, single‑number quantities are calculated using one‑third‑octave bands only. The rating of results of measurements carried out over an enlarged frequency range is dealt with in Annex B.
4.3 Sound spectra The set of sound spectra in one‑third‑octave bands and octave bands to calculate the spectrum adaptation terms shall be as given in Table 4 and shown in Figure 3 and Figure 4. The spectra are A‑weighted and the overall spectrum level is normalized to 0 dB.
4.4 Method of comparison To evaluate the results of a sound insulation measurement in one‑third‑octave bands (or octave bands), the measurement data shall be given to one decimal place 1) . Shift the relevant reference curve in increments of 1 dB (0,1 dB for the expression of uncertainty) towards the measured curve until the sum of unfavourable deviations is as large as possible, but not more than 32,0 dB (measurement in 16 one‑ third‑octave bands) or 10,0 dB (measurement in 5 octave bands).
5 Statement of results
5.1 General The appropriate single‑number quantity R w , R′ w , D n,w or D nT,w and both adaptation terms shall be given with reference to this document. The single number rating for improvement of sound reduction index by linings shall be done as given in Annex D.
5.2 Statement of performance of building elements Calculate the single‑number quantity from one‑third‑octave bands only. State the two spectrum adaptation terms in parentheses after the single‑number quantity, separated by a semicolon.BS EN ISO 717‑1 pdf download.