Different zones where conditions (dust temperature and H nuclei density) for methanol masers are fulfilled or are not fulfilled. The zones shown in different colors are as follows. Gray region: Proper temperature, enclosed by black dashed lines. In regions with lower temperatures ethanol freezes onto dust grains. Higher gas temperatures increase the probability of collisional de-excitation of the methanol molecules. The critical value for gas density is 10⁹ cm⁻³ (white dashed line). Below the white dashed line the gas density is too high for masers. Dark blue region: Frozen methanol. The red region shows the regions in the disk where the methanol gas abundance is optimal for maser occurrence. Thus, the overlap of the gray region and the red region (above the white dashed line) is the region where methanol masers could occur. Zoomed-in images of two regions are added in the middle column to indicate where methanol masers are possible, i.e., the region where temperature, density, and gas methanol abundance favor masers.