ISO 12039:2019

Overview

ISO 12039:2019 specifies the fundamental structure and the key performance characteristics of automated measuring systems (AMS) used to determine the mass concentration of carbon monoxide (CO), carbon dioxide (CO2) and oxygen (O2) in flue gas from stationary sources. The standard covers both extractive and in situ (non‑extractive) systems and describes commonly used analyser principles such as infrared absorption (CO, CO2), paramagnetism, zirconium oxide, electrochemical cells (O2) and tuneable laser spectroscopy (TLS) (CO, CO2, O2). ISO 12039:2019 is intended for continuous monitoring with permanently installed systems and defines requirements for performance testing, calibration and ongoing quality control.

Key topics and technical requirements

• Performance characteristics: Defines attributes to assess AMS performance, including response time, transport time, lack‑of‑fit (linearity), span point and period of unattended operation (maintenance interval).
• Measurement methods: Describes extractive sampling and in situ measurement techniques and acceptable analyser technologies (IR, TLS, paramagnetic, zirconia, electrochemical).
• Sampling and installation: Guidance on sampling location, representative sampling, probe design and sample conditioning to ensure reliable flue gas measurements.
• Calibration and QA/QC: Requirements for calibration using span gases and reference materials, validation procedures, frequency of checks and procedures to determine measurement uncertainty.
• Performance testing: Protocols for performance tests and parallel measurements versus a reference method; Annexes provide method examples, test procedures and uncertainty calculation (see Annexes A–G).
• Data conversion: Procedures for converting volume concentrations to mass concentration and wet‑to‑dry corrections for CO, CO2 and O2 as part of standardized reporting.

Applications and users

ISO 12039:2019 is practical for:

• Environmental regulators and compliance auditors establishing or verifying stack monitoring programs.
• Industrial plant operators and combustion engineers using continuous emissions monitoring for process optimization and regulatory reporting.
• Manufacturers and integrators of AMS equipment seeking to design systems that meet international performance expectations.
• Accredited test laboratories and consultants executing performance tests, validations and uncertainty assessments.

Practical benefits include improved data quality for emissions reporting, robust QA/QC practices, optimized combustion control and consistent measurement traceability.

Related standards

• ISO 14956 - Evaluation of measurement procedures by comparison with required measurement uncertainty.
• Other related ISO standards referenced in the standard’s development: ISO 17179, ISO 13199, ISO 25140, ISO 21258 (measurement of NH3, total VOC, CH4, N2O respectively).

Keywords: ISO 12039:2019, automated measuring systems, CO monitoring, CO2 monitoring, O2 measurement, flue gas, stationary source emissions, extractive systems, in situ analyzers, tuneable laser spectroscopy, QA/QC, calibration, measurement uncertainty.