Overview
ISO 15619:2025 - Reciprocating internal combustion engines - Measurement method for exhaust silencers - defines standardized laboratory and site measurement methods for evaluating the acoustic and aerodynamic performance of exhaust silencers installed on reciprocating internal combustion engines. The second edition (2025) replaces ISO 15619:2013 and applies to silencers for engines within the field of application of ISO 3046‑1; it can also be used for other silencers where no suitable international standard exists.
Key topics and requirements
- Measured parameters
- Sound power level of exhaust noise (from sound pressure measurements)
- Insertion loss (difference in exhaust noise before and after the silencer)
- Power loss ratio and pressure loss (aerodynamic performance indicators)
- Measurement methods
- Laboratory (engineering) method and survey method for controlled and in-situ testing
- Site measurement procedures for field-installed silencers
- Test environment and background noise
- Criteria for acoustic adequacy and background-noise correction, with both relative and absolute criteria defined
- Qualification procedures for test environments (normative annex)
- Instrumentation and procedures
- Requirements for instrumentation, calibration and use (including microphone arrays for laboratory measurements)
- Installation and operating conditions for the engine and silencer under test, including transition pipe guidance and considerations for emission control devices
- Data handling and uncertainty
- Methods for calculating mean time‑averaged sound pressure, corrections for background noise and environment, and conversion to sound power level
- Statements on measurement uncertainty for the engineering and survey methods
- Reporting
- Required information to record and include in the test report, plus annexes covering pressure loss measurement and calculation aids
Applications and users
ISO 15619:2025 is intended for:
- Engine manufacturers and OEMs verifying acoustic and aerodynamic matching of silencers to reciprocating engines
- Silencer designers and acoustic engineers developing and validating silencer performance
- Test laboratories and certification bodies conducting repeatable laboratory and site measurements
- Regulatory agencies and compliance teams assessing noise emissions and reporting standardized results
- Acoustical consultants performing field surveys and noise assessments
Practical uses include product development, type testing, quality control, regulatory compliance, and comparative performance reporting.
Related standards
- ISO 3046‑1 (field of application for reciprocating internal combustion engines)
- Relevant ISO/TC 70 committee publications for engine test methods
Keywords: ISO 15619:2025, exhaust silencers, reciprocating internal combustion engines, sound power level, insertion loss, power loss ratio, laboratory measurement, site measurement, sound pressure, measurement uncertainty.