ISO 17179:2016 PDF

Overview

ISO 17179:2016 defines the structure and performance characteristics of automated measuring systems (AMS) for determining the mass concentration of ammonia (NH3) in flue gas from stationary sources. It covers both extractive and in situ approaches, sampling and sample-conditioning systems, procedures to determine performance characteristics, and recommended quality assurance and calibration practices. The standard is aimed at continuous NH3 monitoring for plants using SNCR/SCR (deNOx) systems and other combustion sources.

Key technical topics and requirements

• Scope and measurand: Continuous measurement of NH3 mass concentration in dry or wet flue gas for process and emission monitoring.
• Measurement principles supported:
  • Differential NOx techniques (ammonia conversion/reaction followed by chemiluminescence (CL) or non-dispersive ultraviolet (NDUV) NOx-difference)
  • Fourier transform infrared (FTIR) spectroscopy
  • Non-dispersive infrared (NDIR) with gas filter correlation (GFC)
  • Tunable laser spectroscopy (TLS)
  • Other equivalent instrumental methods that meet ISO 17179 minimum requirements
• System descriptions: Sampling probes, sample gas conditioning, transport time, analyser modules (extractive vs in situ).
• Performance characteristics: Response time, span/zero calibration, converter efficiencies, lack-of-fit (linearity), measurement uncertainty, period of unattended operation (maintenance interval).
• Procedures: General performance tests, ongoing quality control, calibration/validation with certified reference gases, and methods for determining uncertainty.
• Practical performance examples: Differential NOx CL tested where NO ≈ 50 mg(NO)/m3 and NH3 ≈ 10 mg(NH3)/m3; FTIR, NDIR-GFC and TLS have been used down to about 10 mg(NH3)/m3.
• Normative references: ISO 9169, ISO 14956, ISO 20988 (for performance definitions, uncertainty evaluation and suitability).

Applications and who uses it

• Applications: Continuous emission monitoring, process control and optimization of SNCR/SCR deNOx systems, long-term performance tracking of ammonia slip, regulatory compliance and environmental reporting.
• Primary users: Power plant operators, waste-to-energy and industrial combustion facilities, emissions monitoring equipment manufacturers, QA/QC and environmental compliance engineers, third-party monitoring service providers, and regulators specifying measurement performance.
• Practical benefits: Ensures reliable NH3 measurements for minimizing ammonia slip, optimizing reagent dosing in deNOx systems, and producing defensible monitoring data with documented uncertainty and calibration traceability.

Related standards

• ISO 9169 - Definitions and performance characteristics of automatic measuring systems
• ISO 14956 - Evaluation relative to required measurement uncertainty
• ISO 20988 - Guidelines for estimating measurement uncertainty

Keywords: ISO 17179:2016, ammonia monitoring, NH3 in flue gas, automated measuring system, deNOx, SCR, SNCR, FTIR, NDIR-GFC, TLS, chemiluminescence, emission monitoring, calibration, measurement uncertainty.