Uncertainties of ISO 3382-3 sound pressure level quantities

Abstract

The ISO 3382-3 standard uses the measurable sound pressure based parameters D2,S and Lp,A,S,4 m to describe the acoustic properties of open-plan offices. As yet however, no treatment of the measurement uncertainty of these parameters according to the Guide to the expression of Uncertainty in Measurement (GUM) is to be found in the peer-reviewed literature. This technical note therefore describes how the measurement uncertainty can be declared according to GUM. The mathematical framework presented here can be used and expanded by other laboratories to derive their own uncertainty estimates. It is also applied in this document to 44 measurements yielding combined uncertainties for D2,S of 0.55 dB ≤ $ {\sigma }_{c,{D}_{2,\mathrm{S}}}$ ≤ 0.67 dB and for Lp,A,S,4 m of 0.19 dB ≤ $ {\sigma }_{c,{L}_{p,\mathrm{A},\mathrm{S},4\enspace \mathrm{m}}}$ ≤ 0.83 dB. The implications of this result are discussed with regard to limit values in technical regulations.