scope:

This document specifies a Tuneable Diode Laser Absorption Spectroscopy method for the determination of ammonia content of biogas, natural gas or biomethane This document describes the suitable handling and sampling of pressurised mixtures of ammonia in methane that are applied to several different ammonia measurement systems. The measurement systems comprise of readily available commercial spectroscopic analysers that are specific to ammonia. The method is applicable to the determination of ammonia concentrations from 1 mg/m3 (1,3 ppm volume fraction) to 100 mg/m3 (132 ppm volume fraction). The method has a lower limit of detection of about 0,4 mg/m3 (0,5 ppm volume fraction) NH3 in air with the tested analyser in Annex B.