ISO 10052:2021 Acoustics — Field measurements of airborne and impact sound insulation and of service equipment sound — Survey method.
Table 4 takes account of room volume, and is valid for rooms typical of those in dwellings. However, it may also be used for comparable rooms in other types of buildings.
NOTE 1 Table 4 is based on a statistical evaluation of reverberation times obtained in dwellings, as typically constructed in several European countries in the period 1960 to 1980. The standard deviation of the reverberation indices calculated from these data is approximately 1 dB. Changed construction methods or habitation habits can give rise to systematic deviations.
Alternatively, the reverberation time may be measured according to the specifications for the survey method described in ISO 3382-2:2008, 5.2 in octave bands and the reverberation index may be calculated by using the measured reverberation times according to 13. Measurement of reverberation time can be advantageous if performed only once in a typical room of a building under test which has a large number of identical rooms (for instance in hotels. For noise measurement of service equipment realised in terms of global weighted levels, the reverberation index k is calculated from the averaged reverberation time in the octave bands of 500 Hz, 1 000 Hz and 2 000 Hz.
The tabular values of the reverberation indices are listed in Table 4. Table 4 is valid for a reference reverberation time T0 = 0,5 s and for room sizes of up to 150 m3. Furnished rooms like living rooms, sleeping rooms and rooms of similar volume and furniture are considered in one group. Furnished kitchens and bathrooms are considered separately. Concerning unfurnished rooms the reverberation index depends on the type of construction as listed in Table 3.
It is required that the measurement procedure gives satisfactory reproducibility. This can be determined in accordance with the method shown in ISO 12999-1 and shall he checked from time to time, particularly when a change is made in procedure or instrumentation.
NOTE Numerical requirements for reproducibility of the engineering methods for airborne and impact sound insulation are given in ISO 12999-1. It is estimated that the results from the survey test method and the corresponding engineering method differ within i 2 dB.
7 Expression of results
7.1 Airborne sound insulation
For the statement of the airborne sound insulation, the values of the standardized level difference, the normalized level difference, D. the standardized facade level difference, D2mn the normalized facade level difference D2111 or the apparent sound reduction index R R’45, R’trs shall be given at all frequencies of measurement, to one decimal place, in tabular form and in the form of a curve. Graphs in the test report shall show the value in decibels plotted against frequency on a logarithmic scale, and the following dimensions shall be used:
— 15 mm for an octave band;
— 20 mm for 10 dB.
The use of a form in accordance with Annex A is preferred. Being a short version of the test report it shall include all information of importance regarding the test object, the test procedure and the test results.
For the evaluation of single-number ratings from the octave-band results, see ISO 717-1. It shall be clearly stated that the evaluation has been based on a result obtained by a field survey method.ISO 10052 pdf download.