ISO 6798-3-2022 PDF

Full title and description

Reciprocating internal combustion engines — Measurement of sound power level using sound pressure — Part 3: Survey method for use in situ. This International Standard defines a survey-style, in‑situ measurement procedure for determining the sound power level of reciprocating (piston) internal combustion engines by means of sound pressure measurements around the engine and appropriate corrections and calculations.

Abstract

This document specifies a practical survey method to measure the sound power level of reciprocating internal combustion engines when tested in their installed (in‑situ) environment. It covers test environment criteria, instrumentation and calibration, microphone placement and measurement surfaces, reference sound‑source procedures (substitution/top‑up/juxtaposition), calculation and correction for background noise, uncertainty estimation and required test report information.

General information

• Status: Published.
• Publication date: 11 February 2022 (First edition: 2022-02).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 27.020 (Internal combustion engines); 17.140.20 (Noise emitted by machines and equipment).
• Edition / version: Edition 1 (2022-02).
• Number of pages: 17 pages.

Scope

Applies to reciprocating internal combustion engines within the field of application of ISO 3046-1 and to other internal combustion engines for which no suitable International Standard exists. The standard is intended for survey (in‑situ) measurements rather than detailed engineering test lab procedures; it gives the criteria and methods necessary to obtain representative sound power level values when engines are measured in their installed environment.

Key topics and requirements

• Test environment and background‑noise criteria (minimum ΔL and correction methods).
• Instrumentation requirements, calibration and allowable instrument classes.
• Definition of measurement surfaces, measurement distances and microphone positions for in‑situ surveys.
• Criteria for adequacy of microphone positions and handling of reflections in field conditions.
• Reference sound‑source procedures (substitution, top‑up and juxtaposition methods) for verifying or substituting measurements.
• Calculation methods: averaging of surface time‑averaged sound pressure levels, corrections for background noise, calculation of sound power level and uncertainty estimation.
• Minimum information to be recorded in the test report.

Typical use and users

Used by acoustic consultants, engine manufacturers, test laboratories, site commissioning teams, maintenance engineers and regulatory or compliance bodies that need to assess or document the acoustic output (sound power) of reciprocating internal combustion engines in their installed locations (e.g., generator sets, standby engines, engine‑driven equipment). It is a practical survey method suited for field conditions where laboratory methods are impractical.

Related standards

Part of the ISO 6798 series addressing sound power measurement of reciprocating internal combustion engines. Key related documents include:

• ISO 6798-1:2020 — Reciprocating internal combustion engines — Measurement of sound power level using sound pressure — Part 1: Engineering method (detailed engineering/laboratory method).
• ISO 6798-2:2020 — Reciprocating internal combustion engines — Measurement of sound power level using sound pressure — Part 2: Survey method (additional survey guidance).

Keywords

sound power level, sound pressure, reciprocating internal combustion engine, in‑situ survey, microphone placement, background noise correction, reference sound source, measurement uncertainty, ISO 6798.

FAQ

Q: What is this standard?

A: An ISO International Standard (ISO 6798-3:2022) that specifies a survey (in‑situ) method for measuring the sound power level of reciprocating internal combustion engines using sound pressure measurements.

Q: What does it cover?

A: It covers test environment criteria, instrumentation and calibration, measurement surfaces and microphone positions for field surveys, reference sound‑source methods (substitution/top‑up/juxtaposition), calculation and correction procedures (including background noise correction) and reporting requirements.

Q: Who typically uses it?

A: Acoustic consultants, engine manufacturers and suppliers, test houses, site commissioning and maintenance teams, and regulatory/compliance authorities who need to evaluate engine noise in installed conditions.

Q: Is it current or superseded?

A: ISO 6798-3:2022 was published on 11 February 2022 and is the first edition of Part 3. There is no publicly listed superseding edition as of the date of this summary (2 March 2026); users should verify the current status through the ISO catalogue or their national standards body for the latest confirmation.

Q: Is it part of a series?

A: Yes — it forms part of the ISO 6798 series (examples include ISO 6798-1:2020 — engineering method, and ISO 6798-2:2020 — survey method), which together replace the earlier ISO 6798:1995.

Q: What are the key keywords?

A: sound power level; sound pressure; reciprocating internal combustion engines; in‑situ measurement; survey method; microphone positions; background noise; reference sound source; measurement uncertainty; ISO 6798.