New and updated H i empirical relations. Empirical correlations between accretion luminosity (log(L_acc/L_⊙)) and MIR H i line luminosities (log(L_line/L_⊙)) for six transitions analysed in this work. Each panel displays the linear regression best-fit (dashed black line) with 1σ and 3σ confidence intervals (shaded regions). The best-fit slope and intercept are shown in the bottom-right corner of each panel and listed in Table 1. Blue open squares represent sources without correction for H₂O contamination, while green open circles correspond to sources where the H i line fluxes have been corrected using LTE H₂O models. The pink circles represent the newly measured log(L_acc) values for sources that lack literature values, while the red arrows denote 3σ upper limits for non-detections. The dash-dotted lines in the middle panels indicate the empirical relations reported by Tofflemire et al. (2025) for reference.