Rogier Evertsen of the University of Nijmegen in the Netherlands has demonstrated the suitability of cavity ringdown spectroscopy for the analysis of the combustion products of fuel flames. In a report of the work that appeared as his doctoral thesis, Evertsen demonstrated that the approach can detect OH, CH, HCO, NO and NO₂ from burning methane, oxyacetylene and diesel fuel.

Pulsed cavity ringdown spectroscopy proved sensitive to NO and NO₂ at concentrations of 25 ppm and 3 ppm, respectively, which is within the requirements established in Europe for the detection of NO_x compounds. Evertsen said that combining the technique with other approaches, such as laser-induced fluorescence spectroscopy, may enable the fast and quantitative study of combustion processes.