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1.American National Standard Institute (1999). ANSI S1-1999. Maximum Permissible Ambient Noise Levels for Audiometric Test Rooms ( American National Standard Institute, New York, NY).
2. Beranek, L. L. (1988). Acoustical Measurements ( Acoustical Society of America, Melville, NY).
3. Bjor, O.-H. (1999). “ Measurement of extremely low sound pressure levels,” Gracey, ed. 1. Rev. 0, Norsonic, Lierskogen, Norway, available at (Last viewed September 23, 2013).
4. Ellingson, R. M. , and Bock, G. (2013). “ Design, positional accuracy, and application of straight-path-traversing room-acoustic-measurement system based upon low-cost servo motor and light-weight multi-field microphone,” Proc. Meetings Acoust. 19, 040105.
5. Ellingson, R. M. , and Dille, M. L. (2010). “ Dynamic range considerations when designing PC sound card based audiometric systems to test human hearing,” in Engineering in Medicine and Biology Society (EMBC), 2010 Annual International Conference of the IEEE, Buenos Aires, Argentina, pp. 59075910.
6. Ellingson, R. M. , and Helt, P. V. (2013). “ Planning, design, and installation experience with subterranean installation of a fully anechoic acoustical testing chamber including preliminary performance measures,” Proc. Meetings Acoust. 19, 015084.
7. Frederiksen, E. (1984). “ Microphone system for extremely low sound levels,” in Technical Review ( Brüel & Kjær, Nærum, Denmark), No. 3, pp. 1622.
8. Horonjeff, R. D. , and Ross, J. C. (2002). “ Overcoming instrument noise floors when measuring in quiet environments,” in 2002 International Congress and Exposition on Noise Control Engineering, Inter-noise 2002, Dearborn, MI.
9.International Organization for Standardization (2003). ISO 3745. Acoustics: Determination of Sound Power Levels of Noise Sources Using Sound Pressure—Precision Methods for Anechoid and Hemi-Anechoic Rooms ( International Organization for Standardization, Geneva, Switzerland).
10. Jacobsen, F. , and Molares, A. R. (2009). “ Sound power emitted by a pure-tone source in a reverberation room,” J. Acoust. Soc. Am. 126(2), 676684.
11. Møller, P. K. (1982). “ Measurement of background noise in sound-insulated rooms,” J. Sound Vib. 85(2), 143150.
12.Universität der Künste Berlin (2013). “ Sound calculations->Total level adding of incoherent sound sources,” available at (Last viewed September 20, 2013).
13. Vér, I. L. , Brown, R. M. , and Kiang, N. Y. (1975). “ Low-noise chambers for auditory research,” J. Acoust. Soc. Am. 58(2), 392398.
14. Whittle, L. S. , and Evans, D. H. (1972). “ A new approach to the measurement of very low acoustic noise levels,” J. Sound Vib. 23(1), 6376.
15. Yousefian, N. , Kokkinakis, K. , and Loizou, P. C. (2010). “ A coherence-based algorithm for noise reduction in dual-microphone applications,” in 18th European Signal Processing Conference, EUSIPCO-2010, Aalborg, Denmark, pp. 19041908.

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It can be problematic to measure stationary acoustic sound pressure level in any environment when the target level approaches or lies below the minimum measureable sound pressure level of the measurement system itself. This minimum measureable level, referred to as the inherent measurement system noise floor, is generally established by noise emission characteristics of measurement system components such as microphones, preamplifiers, and other system circuitry. In this paper, methods are presented and shown accurate measuring stationary levels within 20 dB above and below this system noise floor. Methodology includes (1) measuring inherent measurement system noise, (2) subtractive energy based, inherent noise adjustment of levels affected by system noise floor, and (3) verifying accuracy of inherent noise adjustment technique. While generalizable to other purposes, the techniques presented here were specifically developed to quantify ambient noise levels in very quiet rooms used to evaluate free-field human hearing thresholds. Results obtained applying the methods to objectively measure and verify the ambient noise level in an extremely quiet room, using various measurement system noise floors and analysis bandwidths, are presented and discussed. The verified results demonstrate the adjustment method can accurately extend measurement range to 20 dB below the measurement system noise floor, and how measurement system frequency bandwidth can affect accuracy of reported noise levels.


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