PACS 160 μm continuum image of M 33 (Kramer et al. 2010). The boxes corresponding to the regions around the H ii regions BCLMP302, BCLMP691 and the center of M 33 are indicated. The cross shows the position of the dynamical center of M 33. Zoomed in images of the two regions studied, the center and BCLMP302, are shown to the right, with contours indicating the integrated [C ii] intensities observed with PACS (Mookerjea et al. (2011); Nikola et al., in prep.). The known H ii regions in the central region (Gordon et al. 1999) are shown as filled triangles.