ANSI AHRI-300-2008 pdf download Sound Rating and Sound Transmission Loss of Packaged Terminal Equipment
3.6.1 Application Rating. A rating based on tests performed at application Rating Conditions (other than Standard Rating Conditions). 3.6.2 Standard Rating. A rating based on tests performed at Standard Rating Conditions.
3.7 Rating Conditions. Any set of operating conditions under which a single level of performance results and which causes only that level of performance to occur.
3.7.1 Standard Rating Conditions. Rating conditions used as the basis of comparison for performance characteristics. 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:
3.9.1 Shall. Where “shall” or “shall not” is used for a provision specified, that provision is mandatory if compliance with 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, L w . Ten times the logarithm to the base ten of the ratio of the sound power radiated by the source to a reference sound power, expressed in decibels (dB). The reference sound power used in this standard is 1 picowatt (pW).
3.10.1 A-Weighted Sound Power Level, L wA . The logarithmic summation of A-Weighted, one-third octave band Sound Power Levels.
3.11 Sound Quality Indicator (SQI). The calculated metric determined when following the procedure contained in AHRI Standard 1140 for quantifying sound quality whereby measured sound levels are weighted to adjust for psychoacoustic sensitivity to frequency distribution and any discreet tones which may be present and then converted to a single number Sound Quality Indicator.
3.12 Sound Transmission Class (STC). A single-number rating derived from sound transmission loss data in accordance with the method described in ASTM Standard E413.