Top panel: selected lines of trans ethyl methyl ether, t-CH₃CH₂OCH₃, towards Orion KL detected with the IRAM 30 m telescope. Data in the frequency range 124−151 GHz are those of the survey position. From 201 to 293.5 GHz the data are those of the CR (see Sect. 2), where the emission peak of organic saturated O-rich species such as dimethyl ether (CH₃OCH₃) and methyl formate (CH₃OCOH) is located (Favre et al. 2011; Brouillet et al. 2013). A v_LSR of +7.5 km s^-1 is assumed. Bottom panel: selected lines of gauche-trans-n-Propanol, Gt-n-CH₃CH₂CH₂OH, towards Orion KL detected with the IRAM 30 m telescope. A v_LSR of +7.5 km s^-1 is assumed.