IEC 61672-2:2003

Contains changes to the clauses of IEC 651 and a new appendix D with equations for design-goal frequency weightings.

Specifies requirements for sound level meters with respect to their immunity to power- and radio-frequency fields and to electrostatic discharge, and the permitted radio-frequency emissions, together with test procedures to demonstrate conformance to the specifications of this standard.

Describes instruments for the measurement of frequency weighted and time averaged sound-pressure levels. Ensures specified accuracy and stability of an integrating sound level meter and reduces to the practical minimum any differences in equivalent measurements taken with instruments of various makes and models which satisfy the requirements of this standard. Specifies the following characteristics and test methods for integrating sound-level meters: a)integrating and averaging characteristics; b)indicator characteristics; c)overload sensing and indicating characteristics.

IEC 61672-2:2013 provides details of the tests necessary to verify conformance to all mandatory specifications given in IEC 61672-1 for time-weighting sound level meters, integrating-averaging sound level meters, and integrating sound level meters. Pattern-evaluation tests apply for each channel of a multi-channel sound level meter, as necessary. Tests and test methods are applicable to class 1 and class 2 sound level meters. The aim is to ensure that all laboratories use consistent methods to perform pattern-evaluation tests. This second edition cancels and replaces the first edition published in 2003. This second edition constitutes a technical revision, the main technical changes with regard to the previous edition concern conformance to specifications which is now demonstrated when measured deviations from design goals do not exceed the applicable acceptance limits, and when the uncertainty of measurement does not exceed the corresponding maximum permitted uncertainty, with both uncertainties determined for a coverage probability of 95 %. In this document, references to IEC 61672-1, IEC 61672-2, and IEC 61672-3 refer to the second editions unless stated otherwise. Procedures for the pattern-evaluation testing of sound level meters designed to conform to the specifications of IEC 61672-1:2002 were given in IEC 61672-2:2003.