Star-formation rate surface density Σ_SFR of the C1F [O III] emitter sample. We show the values obtained by from SFR(UV) and SFR(Hβ) for every C1F object with S/N(Hβ) > 3. The points of C1F’s SFR(Hβ) are slightly shifted in the horizontal axis for clarity. We compare our results with the best-fit in Shibuya et al. (2015), which assumes SFR = 10 M_⊙ yr⁻¹ and a re-scaled version of the curve in Shibuya et al. (2015) that corresponds to an average of SFR = 4 M_⊙ yr⁻¹, as observed in the C1F+EIGER sample. We also show Σ_SFR for known LyC leakers in the literature (Izotov et al. 2016; Vanzella et al. 2016, 2018, 2022; Kerutt et al. 2024), for which we have estimated SFR(UV) with the same calibration used for COLA1. For COLA1, we show lower limits based on the upper limit of the UV half-light radius.