1、2008 Standard forRequirements for theQualification of ReverberationRooms in the 63 Hz Octave BandARI Standard 280Copyright Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-P
2、rice $10.00 (M) $20.00 (NM) Copyright 2008, by Air-Conditioning, Heating, and Refrigeration InstitutePrinted in U.S.A. Registered United States Patent and Trademark OfficeIMPORTANTSAFETY DISCLAIMERAHRI does not set safety standards and does not certify or guarantee the safety of any products, compon
3、ents orsystems designed, tested, rated, installed or operated in accordance with this standard/guideline. It is stronglyrecommended that products be designed, constructed, assembled, installed and operated in accordance withnationally recognized safety standards and code requirements appropriate for
4、 products covered by thisstandard/guideline.AHRI uses its best efforts to develop standards/guidelines employing state-of-the-art and accepted industrypractices. AHRI does not certify or guarantee that any tests conducted under its standards/guidelines will be non-hazardous or free from risk.Note:Th
5、is standard differs from the 1995 version in that it requires the use of a Reference Sound Source meeting therequirements of and calibrated per ARI Standard 250.Copyright Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or net
6、working permitted without license from IHS-,-,-TABLE OF CONTENTSPAGESection 1. Purpose1Section 2. Scope.1Section 3. Definitions.1Section 4. Reverberation Room Qualification and Testing Procedures.2Section 5. Conformance Conditions 3TABLESTable 1. Broadband Standard Deviation Limits2Table 2. Pure Ton
7、e Standard Deviation 2APPENDICESAppendix A. References Normative .4Appendix B. References Informative4Copyright Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD
8、 280-20081REQUIREMENTS FOR THE QUALIFICATION OFREVERBERATION ROOMS IN THE 63 HZ OCTAVE BANDSection 1. Purpose1.1 Purpose. The purpose of this standard is to establish a method of qualifying reverberation rooms in the 63 Hz Octave Band(50, 63 and 80 Hz One-Third Octave Bands).1.1.1 Intent. This stand
9、ard is intended for the guidance of the industry, including manufacturers, engineers, installers,contractors and users.1.1.2 Review and Amendment. This standard is subject to review and amendment as technology advances.Section 2. Scope2.1 Scope. This standard applies to products rated in the 63 Hz O
10、ctave Band (50, 63 and 80 Hz One-Third Octave Bands)where the sound power is determined from measurements made in a reverberation room by using the comparison method asspecified per ANSI Standard S12.51/ISO: 3741.Section 3. DefinitionsDefinitions. All terms in this document will follow the standard
11、industry definitions in the current edition of ASHRAETerminology of Heating, Ventilation, Air Conditioning and Refrigeration unless otherwise defined in this section.3.1 Broadband Sound. Sound that is random in nature with frequency components distributed over a broad frequency band.Typically pure t
12、ones or periodic disturbances will not be distinguishable in this type of sound spectrum.3.2 Comparison Method. A method used to determine Sound Power Level by comparing the Sound Pressure Level of thesource under test to the average Sound Pressure Level produced in the room by a Reference Sound Sou
13、rce of known sound powerlevel output. The difference in Sound Power Level is equal to the difference in Sound Pressure Level when conditions in the roomare the same for both sets of measurements.3.3 Discrete Frequency Component. A component of the sound field having an instantaneous sound pressure t
14、hat variesessentially as a simple sinusoidal function of time.3.4 Hertz (Hz). A unit of frequency equal to one cycle per second3.5 Low Frequency Data. Low frequency data for purposes of this standard is the 63 Hz Octave Band (50, 63 and 80 HZ One-Third Octave Bands).3.6 Octave Band. A band of sound
15、covering a range of frequencies such that the highest is twice the lowest. The Octave Bandsused in this standard are those defined in ANSI Standard S1.11.3.7 One-Third Octave Band. A band of sound covering a range of frequencies such that the highest frequency is the cube rootof two times the lowest
16、 frequency. The One-Third Octave Bands used in this standard are those defined in ANSI Standard S1.11.3.8 Reference Sound Source (RSS). A portable, aerodynamic sound source that produces a known stable Broadband Sound.3.9 “Shall“ or “Should.“ “Shall“ or “should“ shall be interpreted as follows:Copyr
17、ight Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 280-200823.9.1 Shall. Where “shall“ or “shall not“ is used for a provision specified, that provision is ma
18、ndatory if compliancewith the standard is claimed.3.9.2 Should. “Should“ is used to indicate provisions which are not mandatory but which are desirable as good practice.3.10 Sound Power Level, Lw. Ten times the logarithm to the base ten of the ratio of the sound power radiated by the source to arefe
19、rence sound power, expressed in decibels (dB). The reference sound power used in this standard is 1 picowatt (pW).3.11 Sound Pressure Level, Lp. Twenty times the logarithm to the base ten of the ratio of a given sound pressure to a referencesound pressure of 20 Pa, expressed in decibels (dB).Section
20、 4. Reverberation Room Qualification and Testing Procedures4.1 Low Frequency Reverberation Room Qualification Procedures and Requirements.4.1.1 Procedure for Broadband Qualification. The procedures specified in ANSI Standard S12.51/ISO: 3741shall befollowed for broadband room qualification. One-thir
21、d octave band Sound Pressure Levels shall be measured to the nearest0.1 dB. The test room qualifies for the measurement of Broadband Sound if each of the one-third octave bands computedstandard deviation does not exceed the limits given in Table 1. The RSS used for broadband room qualifications shal
22、l meetthe requirements of ARI Standard 250.Table 1. Broadband Standard Deviation Limits4.1.2 Procedure for Discrete Frequency Qualification. The procedures specified in ANSI Standard S12.51/ISO: 3741shall be followed for one-third octave band discrete frequency room qualification. The discrete frequ
23、encies used in thequalification of the 50, 63, and 80 Hz One-third Octave Bands are equal to those found in ANSI Standard S12.51/ISO:3741 for the 500, 630, and 800 Hz bands divided by 10. The speaker used shall be no greater than 400 mm in diameter.One-third octave band Sound Pressure Levels shall b
24、e measured to the nearest 0.1 dB. The test room qualifies for themeasurement of Discrete Frequency Components if the computed standard deviation does not exceed the limits given byTable 2.Table 2. Pure Tone Standard DeviationOne-ThirdOctave BandCenterFrequency (Hz)Octave BandCenterFrequency (Hz)Stan
25、dardDeviation, (dB)50, 63, 80 63 4One-ThirdOctave BandCenterFrequency (Hz)Octave BandCenterFrequency (Hz)StandardDeviation, (dB)50, 63, 80 63 2Copyright Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted
26、without license from IHS-,-,-ARI STANDARD 280-200834.2 Reverberation Room Physical Requirements.4.2.1 Room Requirements. The reverberation room shall meet the requirements of ANSI Standard S12.51/ISO: 3741.Additionally, the room volume shall not be less than 280 cubic meters.4.3 Reverberation Room S
27、ound Power Testing Procedure.4.3.1 Testing Procedure Using the Comparison Method. To determine the Sound Power Levels in frequency bands below100 Hz, the comparison method as described in ANSI Standard S12.51/ISO: 3741 shall be used. All Sound Pressure Levelsshall be measured in One-third Octave Ban
28、ds to the nearest 0.1 dB. Sound Power Levels shall be computed for each of theOne-third Octave Bands, and the octave band Sound Power Level shall be computed from the one-third octave band SoundPower Levels. The Reference Sound Source used shall meet the requirements of and be calibrated per ARI Sta
29、ndard 250.Section 5. Conformance Conditions5.1 Conformance. While conformance with this standard is voluntary, conformance shall not be claimed or implied forproducts or equipment within the standards Purpose (Section 1) and Scope (Section 2) unless such product claims meet all of therequirements of
30、 the standard and all of the testing and rating requirements are measured and reported in complete compliance withthe standard. Any product that has not met all the requirements of the standard cannot reference, state, or acknowledge thestandard in any written, oral, or electronic communication.Copy
31、right Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ARI STANDARD 280-20084APPENDIX A. REFERENCES NORMATIVEA1 Listed here are all the standards, handbooks, and other publi
32、cations essential to the formation and implementation of thestandard. All references in this appendix are considered part of this standard.A1.1 ANSI Standard S1.11-2004, Specification for Octave-Band and Fractional Octave-Band Analog and DigitalFilters, American National Standards Institute, 25 West
33、 43rd Street, 4th Fl., New York, NY 10036, U.S.A.A1.2 ANSI S12.51-2002/ISO:3741:1999, Acoustics Determination of sound power levels of noise sources usingsound pressure Precision method for reverberation rooms, Nationally Adopted International Standard (NAIS Standard)American National Standards Inst
34、itute, 25 West 43rd Street, 4th Fl., New York, NY 10036, U.S.A.A1.3 ARI Standard 250-2008, Performance and Calibration of Reference Sound Sources, 2008, Air-Conditioning,Heating, and Refrigeration Institute, 4100 N. Fairfax Drive, Suite 200, Arlington, VA 22203, U.S.A.APPENDIX B. REFERENCES INFORMATIVENone.Copyright Air-Conditioning, Heating and Refrigeration Institute Provided by IHS under license with ARI Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-
