NOx Measurement

Many applications require a true NO_x value which means to determine the NO resp. NO₂ concentrations effectively present in the sampled gas. The following factors are of high importance for the NOx determination: quick transport thru the gas sampling system (with smaller diameter by highest pump performance), avoidance of condensate formation (provided by sampling tubing with PTFE sleeve and gas cooler) and in addition gas drying via gas cooler. With ecom instruments, NO_x measurements can be performed with the following measurement principles offering different accuracy levels:

• Electrochemical measurement (NO and NO₂ gas sensors)
• Chemiluminescence (CLD) for NO measurement in combination with an NO₂ gas sensor (electrochemical measurement)
• Chemiluminescence (CLD) in connection with a converter which transforms NO₂ into NO and enables to completely measure the nitrogen oxides content (NO_x).
• Chemiluminescence (CLD) for the NO measurement in connection with photoacoustic spectroscopy (PAS) for the NO2 measurement