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j <br />BOOK • 6 FACE 636 <br />-g- <br />Sound Level Molar and an Octave Band Analyzer that conform to specifications pub- <br />lished by the American Standards Association. (American Standard Sound Level PL-ters <br />for Measurement of Noise and Other Sounds. 224.3-1944, and American Standard Speci- <br />fications for an Octave - Band Filter Set for the Analysis of Noise and Other <br />Sounds, 224.10-1953. American Standards Association, inc.. New York, N.Y.. shall <br />be used.) <br />Table 2 <br />Maximum permissible sound-pressure levels at specified points <br />of measurement for noise radiated continuously from a facility. <br />Frequency Band Dee;bml* <br />C eles r Second Level <br />20 - 75 ......... 69 <br />75 - 150 .......... 54 <br />150 - 300 .......... 47 <br />300 - 600 .5........ 41 <br />fi00 - 1,200 .......... <br />37 <br />1.200 - 2,4oo .......... 34 <br />2,400 - 4,800 .......... 31 <br />4,800 IO.000 .......... 28 <br />10,000 - 20,000 .......... 26 )(to evoid <br />20,000 - 30,000 .......... 25) possible <br />30.000 - 40,000 .......... 24 ) interference <br />40,000 - 50,000 .......... 23 ) with animal <br />experiments) <br />* According to the following formula: <br />Sound Pressure Level in•oecibels equals 10 log P <br />P <br />2 <br />where P2 equals 0.0002 dynes/.. <br />If the noise Is not smooth and continuous. one or more of the corrections <br />in Table 3 below shall be added to or subtracted from each of the decibel levels <br />given above in Table 2. <br />I <br />i <br />i <br />e <br />- - --------------