ISO 7196-1995 PDF

Full title and description

ISO 7196:1995 — Acoustics — Frequency-weighting characteristic for infrasound measurements. Specifies a frequency-weighting characteristic, designated G, for determining weighted sound pressure levels of sound or noise whose spectrum lies partly or wholly within the frequency band from 1 Hz to 20 Hz.

Abstract

The standard defines the G frequency-weighting curve used to produce G-weighted sound pressure levels (LpG, referenced to 20 µPa) for infrasonic measurements (nominal primary band 1 Hz to 20 Hz). It provides the weighting characteristic, recommended normalization and tolerances, and informative guidance on instrumentation and calibration for reliable infrasound measurement.

General information

• Status: Published (International Standard; reviewed and confirmed in 2022).
• Publication date: 9 March 1995.
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 17.140.01 — Acoustic measurements and noise abatement in general.
• Edition / version: Edition 1 (1995).
• Number of pages: 6.

Scope

Specifies the G frequency-weighting characteristic for the determination of weighted sound pressure levels of sound or noise whose spectrum lies partly or wholly within the infrasonic band from 1 Hz to 20 Hz. The weighting is intended as a harmonized method for measurement, reporting and interpretation of infrasonic levels and may be used with sound power and sound intensity measurements (symbolized LWG and LIG when G-weighted).

Key topics and requirements

• Definition of the G-weighting characteristic (designated G) and its nominal frequency response for infrasound measurements.
• Primary frequency band: 1 Hz to 20 Hz; curve normalized to a reference (commonly 0 dB at 10 Hz in practical implementations).
• Specification of tolerances and accuracy requirements for the 1–20 Hz band to ensure comparable measurements.
• Guidance on instrumentation and calibration: microphone characteristics, required low-frequency response, detector/integrator time constants, and calibration procedures tailored to infrasonic measurement.
• Notes on interpretation: typical perceptual thresholds and example levels (G-weighted levels close to ~100 dB near just-perceptible infrasound, with below ~90 dB often not significant for direct perception).

Typical use and users

Used by acoustical consultants, environmental and industrial noise specialists, infrasound researchers, meteorological and geophysical monitoring agencies, regulators and manufacturers of low-frequency microphones and sound level meters. Typical applications include monitoring and assessment of infrasound from natural sources (wind, volcanic activity), industrial processes, HVAC and large machinery, wind turbines, blast and explosion monitoring, and research into human perception of very low-frequency sound.

Related standards

Standards related to acoustic measurement and frequency weighting include ISO standards on equal-loudness contours (ISO 226) and broader acoustics series, and performance standards for sound level meters (IEC/EN standards such as IEC 61672 for sound level meters, which define A, C and Z weightings for audio-frequency measurements). These documents complement ISO 7196 by addressing audible-frequency weighting, instrument performance and calibration practices.

Keywords

G-weighting, infrasound, frequency weighting, weighted sound pressure level, LpG, low-frequency acoustics, infrasound measurement, calibration, ISO 7196.

FAQ

Q: What is this standard?

A: ISO 7196:1995 is an international standard that defines the G frequency-weighting characteristic for measuring and reporting infrasound (1 Hz–20 Hz) sound pressure levels.

Q: What does it cover?

A: It specifies the weighting curve designated G, normalization and tolerances, and provides informative guidance on instrumentation, calibration and interpretation for infrasonic measurements. It is used to produce G-weighted sound pressure levels (LpG) referenced to 20 µPa.

Q: Who typically uses it?

A: Acoustical engineers, environmental monitoring bodies, researchers in low-frequency acoustics and manufacturers of instruments for infrasound measurement use this standard to ensure consistent measurement, reporting and comparison of infrasonic levels.

Q: Is it current or superseded?

A: ISO 7196:1995 remains the published edition and was reviewed and confirmed in 2022, so the 1995 edition is current (confirmed) as of the 2022 review. Users should check national/adopted editions or later ISO activity if they need the very latest status.

Q: Is it part of a series?

A: It is part of the ISO/TC 43 acoustics family of standards (measurement and noise abatement). It complements other weighting and acoustic measurement standards (for example ISO 226 on equal-loudness contours and IEC/ISO standards for sound level meters and instrumentation).

Q: What are the key keywords?

A: G-weighting; infrasound; frequency weighting; LpG; low-frequency acoustics; calibration; ISO 7196.