Historical
ANSI S1.25-1991 (R2007)
American National Standard Specification for Personal Noise Dosimeters
Contains specifications for performance characteristics of personal noise dosimeters that measure the percentage criterion sound exposure. The standard makes provision for three exchange rates: 3 db, 4 db, and 5 db per doubling of exposure time. The standard provides tolerances for the entire instrument including frequency response, exponential averaging (employing SLOW and FAST), threshold, dynamic range, and other characteristics. It specifies that these tolerances be attained by the instrument in a random incidence sound field without the presence of a person wearing the instrument.
Acoustical Society of America [asa]