The American National Standard for measuring noise emitted by business equipment, ANSI S12.10‐1985, includes a new procedure for identifying prominent discrete tones. The procedure is based upon comparing the sound pressure level in the tone to the sound pressure level in the Zwicker bandwidth centered around the tone. In general this new procedure is a substantial improvement over the previous procedure described in ANSI S1.29‐1979, and based on Appendix B of ANSI S.13, which uses sound pressure levels outside the Zwicker handwidth to determine the strength of the masking noise. However, after several months of use with a FFT analyzer it is dear that the S12.10 procedure raises questions that should be addressed. This paper presents examples of tones that sound prominent but do not calculate to be prominent by the new procedure, and examples that do not sound prominent but calculate to be prominent. This paper also presents limitations on use of one‐twelfth‐octave‐band filters to make the measurements required by the S12.10 procedure.