General This standard describes instruments (sound level meters) for the measurement of certain frequency and time weighted sound pressure levels. Types This standard specifies sound level meters of four degrees of precision@ designated Types 0@ 1@ 2 and 3. 1.3 Tolerances The specifications for Types 0@ 1@ 2 and 3 sound level meters have the same centre values and differ only in the tolerances allowed@ Tolerances generally broaden as the type number increases and differ for the various types to a degree which affects manufacturing costs significantly. Characteristics specified This standard specifies the following characteristics of sound level meters: a) directional characteristics; b) frequency weighting characteristics; c) time weighting@ detector and indicator characteristics; d) sensitivity to various environments. Tests specified This standard specifies electrical and acoustical tests to verify compliance with the characteristics specified (see 1.4). It also describes the method for absolute sensitivity calibration.
IEC 60651:2001 history
2001IEC 60651:2001 Sound Level Meters (Edition 1.2; Edition 1:1979 Consolidated with Amendments 1:1993 and 2:2000; Replaced by IEC 61672-1:2002 and IEC 61672-2: 2003)