ISO 8178-1:2020

Overview

ISO 8178-1:2020 - "Reciprocating internal combustion engines - Exhaust emission measurement - Part 1" defines test‑bed measurement systems for gaseous and particulate exhaust emissions from reciprocating internal combustion (RIC) engines. It specifies the measurement methods and instrumentation needed to determine a single weighted value for each exhaust pollutant across combinations of engine speed and load representative of real applications. The standard applies to RIC engines for mobile, transportable and stationary use, excluding road motor vehicles, and covers engines used in earth‑moving machines, generating sets and similar equipment.

Key topics and technical requirements

ISO 8178‑1 lays out technical requirements and procedures for accurate emission measurement on engine test beds. Major topics include:

• General measurement principles - mass-based emission determination, sampling strategies and dilution approaches.
• Exhaust sampling and dilution - raw and dilute gas sampling, dilution system design, and requirements for partial‑flow and full‑flow dilution for particulates.
• Gaseous component determination - analyzer types and performance expectations for CO, CO2, O2, HC/NMHC, NOx, SO2, NH3, N2O, formaldehyde, methanol and air‑to‑fuel measurements.
• Particulate determination - particulate mass sampling probes and filters, pre‑classifiers, transfer lines, weighing procedures, and particle number measurement considerations.
• Engine and ambient measurement equipment - dynamometer, torque/speed sensors, pressure and temperature transducers, and flow metering for fuel, intake air and exhaust.
• Calibration and verification - calibration gases, verification checks, analyzer linearity, system response and leak tests, and regular performance checks.
• Data recording and control - requirements for measurement system integration, data logging and traceability.

Practical applications

ISO 8178‑1 is used to:

• Establish repeatable, comparable emission results from laboratory engine tests.
• Support development and validation of engine aftertreatment and emission control technologies.
• Provide test procedures for compliance verification, R&D, certification testing and regulatory assessment for non‑road engines.
• Guide design of test laboratories and selection of analyzers, dilution systems and particulate sampling equipment.

Who should use this standard

• Engine manufacturers and design engineers for non‑road and stationary engines
• Emissions test laboratories and certification bodies
• Equipment suppliers (analyzers, dilution systems, dynamometers)
• Regulatory authorities and researchers concerned with non‑road engine emissions

Related standards

• ISO 8178 series (other parts such as ISO 8178‑4 for test cycles and test procedures) - see ISO 8178 family for full context.

Keywords: ISO 8178-1, exhaust emission measurement, reciprocating internal combustion engines, test-bed, gaseous emissions, particulate emissions, dilution system, particle number, emission analyzers, calibration.