Fig. 3. Molar HOM yields at 300 K as a function of reacted VOC, measured in the Helsinki flow reactor at a residence time of 3 s.

The error bars, included only for the last point of each trace, show the uncertainty of the HOM measurement. No multi-generation OH oxidation takes place due to the high VOC concentration (10 ppm) and the short residence time. Linear alkanes did not produce observable HOM signals under these conditions.