Résumé : This paper shows that, to a certain extent, remote atmospheric mass spectrometry can be used to identify signature fragments, which are able to predict the final surface chemistry of plasma-deposited organic hydrophilic or hydrophobic coatings, to propose polymerization mechanisms and to predict coating contamination. Examples are given for the plasma polymerization of anhydrides and organic acids for polar coatings and for the polymerization of fluorinated precursors for hydrophobic coatings. To predict the final surface chemistry of hydrophilic coatings, we show that by tracking the evolution of the CO+ and CO2 + fragments in the plasma phase, one can deduce the relative amount of polar functions on the final coating surface. Similarly, the change in intensities of the various CFx + fragments during the plasma polymerization of hydrophobic coatings is correlated with the relative amount of such CFx groups in the coating. For the same coatings, when CO2 +, COF+, and COF2 + fragments are detected in the gas phase, the final coating will be contaminated. The possibilities, as well as some limits of this approach, are discussed.