IRDC18223: the color scale shows in the left, middle and right panel the emission from C¹⁸O(2–1), [CI] and [CII], respectively. The integration regimes for the three color images are are [42; 49]. [43; 49] and [43; 55] km s^-1. The white and cyan contours in the left panel correspond to the velocity components at [53.0; 56.0] and [46.9; 48.0] km s^-1. The black contours always show the 1.2 mm continuum emission (Beuther et al. 2002) starting at 3σ level of 36 mJy beam^-1 and continuing in 3σ steps. The arrows in the middle and right panel outline the direction of a bipolar outflow studied by Fallscheer et al. (2009).