Measurement uncertainty in airborne sound insulation and single-number quantities using sound pressure and sound intensity approached

The paper presents an analytical approach in calculating the measurement uncertainty in airborne sound insulation single-number quantity (SNQ). The work ascertains the magnitude of uncertainty difference for single-number quantities considering the sound pressure approach, sound intensity approach and a combined approach utilizing sound intensity method for low frequency measurements (50 to 160 Hz) and sound pressure for the frequency range of 200 Hz to 5 kHz. The work presents two case studies: one utilizing the standard deviation of reproducibility recommended in ISO 12999-1, ISO 15186-1 and ISO 15186-3 standards and the other utilizing the standard deviation of reproducibility reported by Dijckmans and Vermeir in 2013. The analytical results suggest that a combined approach i.e. sound intensity in range 50 to 160 Hz as per ISO 15186-3 and sound pressure in range 200 Hz to 5 kHz is most suitable for reducing the measurement uncertainty in single number quantities in the frequency range 50 Hz to 5 kHz.