ISO/TC 146/SC 1/WG 34 - Revision of ISO 10849 and ISO 7935

This document specifies a method for the determination of nitrogen oxides (NOx) in flue gas of stationary sources and describes the fundamental structure and the key performance characteristics of automated measuring systems. The method allows continuous monitoring with permanently installed measuring systems of NOx emissions. This document describes extractive systems and in situ (non-extractive) systems in connection with a range of analysers that operate using, for example, the following principles: — chemiluminescence (CL); — infrared absorption (NDIR); — Fourier transform infrared (FTIR) spectroscopy; — ultraviolet absorption (NDUV); — differential optical absorption spectroscopy (DOAS); Other equivalent instrumental methods such as laser spectroscopic techniques can be used provided they meet the minimum performance requirements specified in this document. The measuring system can be validated with reference materials, in accordance with this document, or comparable methods. Automated measuring system (AMS) based on the principles listed above has been used successfully in this application for the measuring ranges as shown in Annex F.

This document specifies the fundamental structure and the most important performance characteristics of automated measuring systems for carbon monoxide (CO), carbon dioxide (CO2) and oxygen (O2) to be used on stationary source emissions. This document describes methods and equipment for the measurement of concentrations of these gases. The method allows continuous monitoring with permanently installed measuring systems of CO, CO2 and O2 emissions. This international standard describes extractive systems and in situ (non-extractive) systems in connection with analysers that operate using, for example, the following principles: — infrared absorption (CO and CO2); — paramagnetism (O2); — zirconium oxide (O2); — electrochemical cell (O2); — tuneable laser spectroscopy (TLS) (CO, CO2 and O2). Other instrumental methods can be used provided they meet the minimum requirements proposed in this document. Automated measuring systems (AMS) based on the principles above have been used successfully in this application for measuring ranges which are described in Annex G.