in common to most NMVOCs in a similar way as CH4. As for aldehydes, nearly the same form of the chain reaction mechanism can also be applied. The oxidation reactions with O3 and NO3 for alkenes and the reaction with NO3 for aldehydes are also important. In this section, the oxidation reaction mechanisms of hydrocarbons and aldehydes with OH, O3 and NO3 are summarized.