ANSI/ASA S1.22-1992 (R2007)
Vendor Note: For rectangular cartesian graphs in which a level (in decibels) of an acoustical quantity is plotted against frequency on alogarithmic scale, the scale proportions shall be those for which the length for a 10:1 frequency ratio on the abscissa is equal tothe length for a level difference of 25, 50, or 10 decibels (dB) on the ordinate. For polar diagrams in which an absolute orrelative level (in decibels) is shown increasing outward along a radius on a linear scale, a reference circle shall be identifiedwhose radius is a difference in level of 50 dB (alternatively, 25 dB), and such that maximum level is preferably plotted within 5dB (alternatively, 2.5 dB) of the reference circle. For polar diagrams of relative level, the level assigned to the reference circle ispreferably 0 dB; the angle assigned to the reference direction is preferably zero degrees. The preferred size for one decibel is 2,1, or 5 mm.
Note: This is a withdrawn item.