ISO 21877:2019 PDF

Overview

ISO 21877:2019 - Stationary source emissions - Determination of the mass concentration of ammonia - Manual method - specifies a validated, manual sampling and analysis method for measuring the mass concentration of ammonia (NH3) in waste gas from industrial and agricultural plants. The method measures all volatile compounds that form ammonium ions in the absorption solution, reporting the volatile ammonia content. ISO 21877:2019 has been field-validated in the approximate range 8 mg/m3 to 65 mg/m3 (at standard conditions) and can be used at lower concentrations depending on sampling volume, duration and analytical detection limits.

Key topics and requirements

• Sampling system: requirements for both isokinetic and non‑isokinetic sampling, sampling ports, measurement planes and measurement points.
• Analytical methods: supported laboratory techniques include spectrophotometry, continuous flow analysis (CFA) and ion chromatography (described in informative annexes).
• Absorption solution: collection of volatile NH3 and other volatile ammonium-forming species that dissociate during sampling.
• Performance characteristics: specifications for sampling and analytical performance, limits of detection, repeatability and uncertainty.
• Uncertainty budget: guidance to establish combined and expanded uncertainty using GUM principles (ISO/IEC Guide 98-3) and example calculations (informative annexes).
• Field procedures: measurement planning, sampling strategy, field blanks, leak tests, sample transport and storage, and calculation/reporting of results.
• Validation and use: method validated by field tests (Annex A) and intended as an independent method of measurement (equivalent to an SRM under EN 14181) for intermittent monitoring and AMS calibration/validation.

Applications and who uses it

• Environmental and air quality professionals performing intermittent monitoring of ammonia emissions from combustion plants, fertilizer production, waste incineration, agricultural facilities and other stationary sources.
• Laboratories and field teams conducting stack sampling and analytical determination of NH3 mass concentration.
• Regulatory bodies and plant operators using ISO 21877:2019 to calibrate or validate permanently installed automated measuring systems (AMS) in accordance with ISO 17179 and EN 14181.
• Compliance teams establishing measurement uncertainty, reporting protocols and quality assurance for emissions inventories and permit compliance.

Related standards and references

• ISO 17179 - performance characteristics of automated ammonia measuring systems (AMS)
• ISO 7150-1, ISO 11732, ISO 14911 - referenced analytical methods for ammonium determination and ion chromatography
• ISO/IEC Guide 98-3 (GUM) - uncertainty of measurement

ISO 21877:2019 is essential for reliable, standardized measurement of ammonia slip and emissions, providing clear procedures for sampling, analysis and uncertainty that support regulatory compliance, AMS validation and environmental monitoring.