IEC 61252:2025

IEC 61252:2025 specifies
– performance specifications for personal sound exposure meters,
– details of the tests necessary to verify conformance to all mandatory specifications for the purpose of pattern evaluation, and
– procedures for periodic testing of a personal sound exposure meter.
Personal sound exposure meters conforming to the requirements of this document have a specified frequency response for sound incident on the microphone from all directions.
This document is applicable to instruments that are designed to be worn on a person in a configuration specified by the manufacturer for the measurement of sound immission resulting from steady, intermittent, fluctuating, irregular, or impulsive sounds. For reproducibility of results, specifications and tests for the response to sound waves apply without an operator present in the sound field.
Pattern evaluation tests and periodic tests described in this this document apply to personal sound exposure meters for which the manufacturer claims conformance to the specifications given in this document.
IEC 61252:2025 cancels and replaces the first edition published in 1993, Amendment 1:2000, and Amendment 2:2017. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) personal sound exposure meters are required to provide indications of time-averaged sound level and peak sound level;
b) sound exposure is an optional quantity for indication;
c) specifications for physical quantities that do not follow the principle of equal-energy exchange rate have been added;
d) specifications for directional response have been added;
e) specifications for frequency weightings apply to the relative diffuse-field frequency response;
f) determination of conformance to specifications takes account of uncertainties of measurement;
g) detailed requirements for pattern-evaluation tests and periodic testing have been added.