Pure Tones definition

Pure Tones. Pure tones shall mean any noise in which a single frequency stands out contains a “pure tone.” A pure tone shall exist if the one-third octave band sound-pressure level in the band with the tone exceeds the arithmetic average of the sound-pressure levels of the two contiguous one-third octave bands by 5 dB for center frequencies of 500 Hertz and above, and by 8 dB for center frequencies between 160 and 400 Hertz, and by 15 dB for center frequencies less than or equal to 125 Hertz.
Pure Tones means any sound for which the one-third octave band sound-pressure level in the band with the tone exceeds the arithmetic average of the sound-pressure levels of the two contiguous one-third octave bands by five dB for center frequencies of 500 Hertz and above, or by eight dB for center frequencies between 160 and 400 Hertz, or by 15 dB for center frequencies less than or equal to 125 Hertz.