Position of the DIG regions in our sample in the [N II] BPT (left), [S II] BPT (middle), and [O I] BPT (right) colour-coded by the median EW(Hα). We excluded NGC 1365 because of its prominent AGN cone. Demarcation lines from the literature are shown as dashed (Kewley et al. 2001, 2006), dotted (Kauffmann et al. 2003), and solid black lines (Law et al. 2021). The colour bar for EW(Hα) highlights the transition region between the 16th and 84th percentiles of the EW(Hα) distribution of all regions.