This paper explores the potential of using the Arrhenius diagrammatic analysis of dynamic in situ 9 GHz c.w.e.p.r, data taken in constant time-constant temperature intervals to calculate 'activation' energies characterizing stable free radical reactions that contribute to the various stages of the low-temperature oxidation process. The measurements were made on an Alberta foothills (Luscar) h.v. bituminous coal. The most evident thermal feature of these diagrams is the existence of two and three linear regions characteristic of first-order reactions for samples of this coal when subjected to dry air and nitrogen gas flow, respectively. The two regions with positive Arrhenius slopes are similar for both gases. The third region, with a negative Arrhenius slope, appears in the temperature interval 293-323 K and is correlated with the decomposition of peroxygen radicals. The 'activation' energies in this region depend on the initial moisture content of the coal samples. The initial positive-slope region has a much larger Arrhenius slope than the second highertemperature region when the samples are subjected to dry air and nitrogen gas flow. Hydroperoxygen decomposition reactions appear to dominate in the former region, which create other free radicals and produce primarily gaseous oxidation products, whereas the reactions in the latter region produce solid oxidation products with much lower 'activation' energy values. It shows that this analysis can be used to provide unambiguous identification of the role that moisture and the presence of oxygen play in determining the sequence of different reactions involving stable free radicals that contribute to the low-temperature oxidation of coal.