Correlation between the H₂O/FIR and FIR luminosities for a sample of galaxies in the literature, compared to SPT 0346-52. Green squares represent local starburst galaxies observed with Herschel (Liu et al. 2017), grey circles show local ULIRGS and blue circles show high-redshift Hy/ULIRGs (Yang et al. 2016). The large red square shows the location of SPT 0346-52. The uncertainties in some of these measurements are smaller than the size of each data point. SPT 0346-52 follows the trend, suggesting the presence of radiative pumping of the H₂O molecules.