1207.2.1 Masonry.
BC § 1207.2.1
The sound transmission class of concrete masonry and clay masonry assemblies shall be calculated in accordance with TMS 302 or determined through testing in accordance with ASTM E 90. Table 1207.2.1Maximum Sound Pressure Levels for Machine Rooms Adjacent to Dwelling Units, Measured in the Dwelling Unit Octave Bands, Hz Mid-FrequencyMax. Sound Pressure Level db a db re 0.0002 microbars Octave Bands, Hz Mid-FrequencyMax. Sound Pressure Level db a db re 0.0002 microbars 63 61 125 53 250 46 500 40 1,000 36 2,000 34 4,000 33 8,000 32 a. The maximum sound pressure levels shall be reduced 5 db in any octave band where the equipment data indicate pure tone generation. The presence of pure tones may be determined by means of one-third octave band analysis. The criterion for a significant pure tone component shall be an audible pure-tone sound together with an increase of the sound pressure level in the corresponding one-third octave band above the mean of the two adjacent one-third of at least: Center frequency of one-third octave band:40/125 160/250 215/500 630/1,000 1,000/10,000 Increase in sound pressure level (db): 6 4 3 2 1 1/2
