The method to determine the emission sound pressure level using sound intensity measurements is developed and tested using 3 different sound sources measured at several positions in 8 environments with K_(3A) between 0,1 dB and 13 dB where all results are related to the reference sound pressure levels determined in a semi-anechoic chamber. These tests are carried out for 4 sound intensity methods different in handling the spatial probe orientation. In respect to the absolute deviations of the sound intensity level values against the reference sound pressure levels and taken into consideration the standard deviation of reproducibility and repeatability the 4 methods show no significant distinctions but the three-component method L_(l,xyz) can be recommended due to its advantages in practical handling. For L_(l,xyz) three sound intensity components are measured in the three cartesian directions one after another and the resulting magnitude of the intensity vector is calculated according equation (1).
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