ANSI AHRI-280-2008 pdf download Requirements for the Qualification of Reverberation Rooms in the 63 Hz Octave Band
1.1 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 standard 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. Scope
2.1 Scope. This standard applies to products rated in the 63 Hz Octave 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 as specified per ANSI Standard S12.51/ISO: 3741.
Section 3. Definitions
Definitions. All terms in this document will follow the standard industry definitions in the current edition of ASHRAE Terminology 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 tones 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 the source under test to the average Sound Pressure Level produced in the room by a Reference Sound Source of known sound power level output. The difference in Sound Power Level is equal to the difference in Sound Pressure Level when conditions in the room are the same for both sets of measurements.
3.3 Discrete Frequency Component. A component of the sound field having an instantaneous sound pressure that varies essentially as a simple sinusoidal function of time.
3.4 Hertz (Hz). A unit of frequency equal to one cycle per second
3.5 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 covering a range of frequencies such that the highest is twice the lowest. The Octave Bands used 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 root of two times the lowest 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: