Measurement Precision Under Repeatability Conditions of a Batch of Sound Power Assessment for Blenders in Reverberation Room

Open access

Abstract

A set of sound power assessments was performed to determine measurement precision in specified conditions by the comparison method in a reverberation room with a fixed position array of six microphones. Six blenders (or mixers) and, complementary, a reference sound source were the noise sources. Five or six sound power calculations were undertaken on each noise source, and the standard deviation (sr) was computed as “measurement precision under repeatability conditions” for each octave band from 125 Hz to 8 kHz, and in dB(A). With the results obtained, values of sr equal 1.0 dB for 125 Hz and 250 Hz, 0.8 dB for 500 Hz to 2 kHz, and 0.5 dB for 4 kHz and 8 kHz. Those can be considered representative as sound power precision for blenders according to the measurement method used. The standard deviation of repeatability for the A-weighted sound power level equals 0.6 dB. This paper could be used for house or laboratory tests to check where their uncertainty assessment for sound power determination is similar or not to those generated at the National Metrology Institute.

1. ABNT (1997), ABNT NBR 13910-1:1997 - Test guidelines for the determination of acoustic noise of household and similar electrical appliances - Part 1: General requirements [in Portuguese], Brazilian Association of Technical Standards (ABNT), Sao Paulo, Brasil.

2. ABNT (1998a), ABNT NBR 13910-2-3:1998 - Test guidelines for the determination of acoustic noise of household and similar electrical appliances - Part 2: Particular requirements for blenders [in Portuguese], Brazilian Association of Technical Standards (ABNT), Sao Paulo, Brasil.

3. ABNT (1998b), ABNT NBR 13910-3:1998 - Test guidelines for the determination of acoustic noise of household and similar electrical appliances - Part 3: Procedure for determining and verifying declared noise emission values [in Portuguese], Brazilian Association of Technical Standards (ABNT), Sao Paulo, Brasil.

4. Araujo M.A.N., Azevedo J.A., Medeiros S. (1995), The Brazilian Noise Labeling Program, International Conference on Noise Control Engineering, Newport Beach, 1445-1449.

5. Batko W.M., Stępień B. (2014), Type A Standard Uncertainty of Long-Term Noise Indicators, Archives of Acoustics, 39, 1, 25-36.

6. BIPM (2008), BIPM/JCGM100:2008, Evaluation of Measurement Data - Guide to the Expression of Uncertainty in Measurement, Geneve.

7. BIPM (2012), BIPM/JCGM200:2012, The International Vocabulary of Metrology, Basic and General Concepts and Associated Terms (VIM), BIPM, IEC, IFCC, ILAC, ISO, IUPAC, IUPAP and OIML, pp. 90.

8. CONAMA (1994), National Council of Environment, CONAMA 020/94, Brasil.

9. Costa-Felix R.P.B. (2006), Type B uncertainty in sound power measurements using comparison method, Measurement, 39, 2, 169-175.

10. EEC (1986), Council Directive 86/594/EEC of 1 December 1986 on airborne noise emitted by household, appliances, Official Journal of the European Communities, No. L 344, 06DEC1986.

11. EPD-HK (2006), A concise guide to the noise control ordinance, Environmental Protection Department of Hong Kong (EPD-HK), 9th Edition, APR2006.

12. Hanes P. (1992), Measurement uncertainties in the determination of machinery sound power levels, Euronoise 92, Book 2, 285-291.

13. HSE (2001), Noise emission in the environment by equipment for use outdoors (NEEEOR), Guidance notes on the UK Regulations, 1st Edition, JUN2001.

14. IEC (2006), IEC 60704-3:2006 - Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 3: Procedure for determining and verifying declared noise emission values, International Electrotechnical Commission, Geneva, Switzerland.

15. IEC (2010), IEC 60704-1:2010 - Household and similar electrical appliances - Test code for the determination of airborne acoustical noise - Part 1: General requirements, International Electrotechnical Commission, Geneva, Switzerland.

16. ISO (1985), ISO 7574-2:1985 - Acoustics - Statistical methods for determining and verifying stated noise emission values of machinery and equipment - Part 2: Methods for stated values for individual machines, International Organization for Standardization, Geneva, Switzerland.

17. ISO (1994a), ISO 5725-2:1994 - Accuracy (trueness and precision) of measurement methods and, results - Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method, International Organization for Standardization, Geneva, Switzerland.

18. ISO (1994b), ISO 3743-2:1994 - Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering methods for small, movable sources in reverberant fields - Part 2: Methods for special reverberation test rooms, International Organization for Standardization, Geneva, Switzerland.

19. ISO (2010a), ISO 3743-1:2010 - Acoustics - Determination of sound power levels of noise sources - Engineering methods for small, movable sources in reverberant fields - Part 1: Comparison method for hard-walled test rooms, International Organization for Standardization, Geneva, Switzerland.

20. ISO (2010b), ISO 3744:2010 - Acoustics - Determination of sound power levels of noise sources using sound pressure - Engineering method in an essentially free field over a reflecting plane, International Organization for Standardization, Geneva, Switzerland.

21. Jonasson H.G., Stenhoff A. (1992), Declaration and verification of noise emission values, International Congress on Noise Control Engineering, Toronto, Canada, 1245-1248.

22. Lubman B. (1974), Precision of reverberant sound power measurements, J. Acoust. Soc. Am., 56, 2, 523533.

23. Lundeby A., Vigran T.E., Bietz H., Vorlander M. (1995), Uncertainties of Measurements in Room Acoustics, Acta Acustica united with Acustica, 81, 344-355.

24. Massacesi A., Paone N., Rossi G.L., Tomasini E.P. (1997), Uncertainty and compatibility analysis of acoustics power determination by intensity and pressure measurement techniques, XIV Congresso Brasileiro de Engenharia Mecanica, Bauru, SP, Brasil.

25. NSW (2010), NWS Department of Environment, Climate Change and Water for the Working Group on Noise Labelling, Australian and New Zealand Noise Labelling and Limit Scheme - Recommendations for Portable Equipment, MAY2010.

26. Paris J.L., Tabuenca B.S. (2000), Comparison of the noise level of a washing machine measured by two methods: ISO 3744 and ISO 9614, 7th Int. Congress on Sound and Vibration, Garmisch, Germany, 2511-2518.

27. Payne R.C., Hanes P. (1993), An investigation of measurement uncertainties in the determination of machinery sound power levels, International Congress on Noise Control Engineering, 329-334.

28. Payne R.C., Simmons D.J. (1996), Measurement uncertainties in the determination of the sound power level of machines, International Congress on Noise Control Engineering, Liverpool, Book 5, 2713-2718.

29. Payne R.C., Simmons D.J. (2000), Assessment of reproducibility uncertainties for use in international standards on the determination of sound power, National Physical Laboratory, UK, Report CMAM 51, p. 103.

30. Vorlander M., Bietz H. (1994), Comparison of Methods for Measuring Reverberation Time, Acustica, 80, 205-214.

31. Vorlander M., Raabe G. (1995), Calibration of reference sound sources, Acustica, 81, 247-263.

Archives of Acoustics

The Journal of Institute of Fundamental Technological of Polish Academy of Sciences

Journal Information


IMPACT FACTOR 2016: 0.816
5-year IMPACT FACTOR: 0.835

CiteScore 2016: 1.15

SCImago Journal Rank (SJR) 2016: 0.432
Source Normalized Impact per Paper (SNIP) 2016: 0.948

Cited By

Metrics

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 233 168 11
PDF Downloads 84 67 10