IEC 62585-2012 PDF

Full title and description

St IEC 62585-2012 — Electroacoustics: Methods to determine corrections to obtain the free-field response of a sound level meter. This International Standard specifies methods for determining frequency-dependent correction values (case reflections, diffraction, microphone response deviations, windscreens and accessories) and associated measurement uncertainties so that periodic and pattern evaluation tests of sound level meters can be performed consistently.

Abstract

IEC 62585:2012 provides procedures to quantify and report the corrections needed to convert an instrument measurement configuration to an equivalent free-field response over a specified frequency range. It describes methods to determine corrections for the effects of the meter case and microphone mounting, typical microphone frequency-response deviations (where individual microphone measurement is not available), the influence of windscreens and other accessories, and guidance on measurement uncertainty including maximum permitted expanded uncertainties in some instances. The standard is intended for use by manufacturers and testing laboratories performing pattern evaluation and periodic tests (in conjunction with IEC 61672 series).

General information

• Status: Published / Active (national and regional adoptions exist).
• Publication date: 25 July 2012 (IEC publication date; often listed as 2012-07-25).
• Publisher: International Electrotechnical Commission (IEC), TC 29 Electroacoustics.
• ICS / categories: 17.140.50 — Electroacoustics.
• Edition / version: Edition 1.0, 2012.
• Number of pages: 81 pages (official IEC publication).

Scope

This standard gives methods to determine the corrections required over a range of frequencies so that periodic tests (as defined in IEC 61672-3) or pattern-evaluation checks (IEC 61672-2) yield results representative of free-field performance. It covers corrections for meter case reflections and diffraction, typical microphone frequency-response deviations when individual microphone calibration is not available, and the effects of windscreens and other accessories; it also addresses measurement uncertainty and, where appropriate, maximum permitted expanded uncertainty values. The standard is applicable to conventional and integrating sound level meters submitted for pattern evaluation or periodic testing.

Key topics and requirements

• Methods to determine frequency-dependent corrections to obtain free-field response (case reflections, diffraction around microphone and case).
• Procedures to account for typical microphone frequency-response deviations when individual microphone measurement is not feasible.
• Evaluation of the influence of windscreens and other accessories on microphone frequency response and inclusion of those corrections in the test configuration.
• Guidance on measurement uncertainty: components to consider and, in some cases, maximum permitted expanded uncertainties for manufacturers or laboratories.
• Submission and inspection recommendations for pattern/periodic tests (examples: minimum numbers of calibrators, microphones and actuators to be submitted for testing).
• Mounting and positioning recommendations (rod diameter, minimum distances, mounting angles) to minimise unwanted effects during measurement.

Typical use and users

Primary users are sound level meter manufacturers (for establishing adjustment and correction values during design and documentation) and accredited testing laboratories performing pattern evaluation (IEC 61672-2) and periodic tests (IEC 61672-3). Secondary users include national metrology institutes, accreditation bodies, acoustic consultants and regulators who reference instrument performance and uncertainty for compliance and verification purposes.

Related standards

IEC 62585 is intended to be used together with the IEC 61672 series (Sound level meters — Parts 1, 2 and 3) for pattern evaluation and periodic tests. Other related electroacoustics standards referenced in practice include microphone standards (for example IEC 61094 series) and national/adopted versions such as EN 62585:2012 and related regional adoptions.

Keywords

Electroacoustics, sound level meter, free-field response, corrections, microphone frequency response, diffraction, case reflections, windscreen, measurement uncertainty, IEC 61672, periodic tests, pattern evaluation.

FAQ

Q: What is this standard?

A: IEC 62585:2012 is an International Standard that specifies methods to determine corrections needed to obtain the free-field frequency response of a sound level meter and to quantify the associated uncertainties.

Q: What does it cover?

A: It covers procedures for determining frequency-dependent corrections for case reflections and diffraction, typical microphone response deviations, the effects of windscreens and accessories, mounting/positioning recommendations, submission guidance for tests, and guidance on uncertainty evaluation (including some maximum permitted expanded uncertainties). The standard supports consistent application of IEC 61672-2 and IEC 61672-3 tests.

Q: Who typically uses it?

A: Manufacturers of sound level meters, accredited test laboratories (pattern evaluation and periodic testing), national metrology and accreditation bodies, acoustic consultants and regulatory authorities involved in noise measurement and instrument verification.

Q: Is it current or superseded?

A: IEC 62585:2012 is the first edition published in July 2012 and is listed as the current IEC publication (stability/target date information appears on the IEC catalogue entry). Users should check the IEC catalogue or their national standards body for any amendments or national adoptions since 2012.

Q: Is it part of a series?

A: It is a stand-alone IEC standard that is intended to be used in conjunction with the IEC 61672 series (Parts 1–3) for sound level meters; it complements periodic and pattern-evaluation test procedures rather than forming a numbered part of the 61672 series itself.

Q: What are the key keywords?

A: Free-field response, corrections, sound level meter, microphone response, diffraction, case reflections, windscreen, measurement uncertainty, periodic tests, pattern evaluation.