The system shall comprise one HFID analyser for the measurement of the unburned hydrocarbons (HC), and NDIR analyser for measurement of carbon monoxide (CO) and a CLA, HCLA or equivalent analyser for measurement of oxides of nitrogen (NOx). Due to the heavy hydrocarbons present in the diesel exhaust, the HFID system shall be heated and maintained at a temperature of 453 to 473 K (180 to 200 °C).
