Long-term measurements of surface UV intensity that have undergone quality control procedures are very limited. The database presented here contains selected biologically weighted daily radiation exposures (for the erythema appearance, previtamin D3 synthesis, and clearing of psoriatic lesions) based on monitoring of erythema irradiance in the Central Geophysical Laboratory of the Institute of Geophysics of the Polish Academy of Sciences, Belsk (20.79°E, 51.84°N, 188 m amsl) from January 01, 1976 to December 31, 2023. The following broadband instruments were involved in continuous measurements of the erythemal irradiance: Robertson-Berger (1975-1992 after correction for temperature effects), Solar Light model 501 (1993-1994 with No. 927, 1995-2013 with No. 2011) and Kipp-Zonen UV-AE-T No. 30616 (KZ) from September 2013 to the present. The homogenization procedure applied to the pre-September 2013 data consisted of a comparison of the measured daily erythemal radiant exposure (RE) during sunny days with the corresponding hypothetical daily erythemal RE calculated by the tropospheric ultraviolet and visible radiation (TUV) model (https://www2.acom.ucar.edu/modeling/tuv-download). Subsequently, a comparison of the daily erythemal RE measured by KZ and the collocated Brewer Mark II spectrophotometer No. 64 during cloudless days provided the calibration of the biometer measurements. Using the corrected data, a regression model of the daily erythemal RE was built (separately for the years 1976-1992, 1993-2013 and 2014-2023) using the following explanatory variables: total column ozone content from the collocated Dobson spectrophotometer No.84, solar zenith angle at the noon, and the clearness index from measurements of total solar radiation (300-3000 nm) with collocated pyranometers. If there was a large difference (exceeding the 2-sigma level) between the measured daily RE value and the value obtained from the regression model, the data was flagged as data of uncertain quality. Transfer coefficients from daily erythemal RE to other biologically weighted daily RE, based on the methodology of Czerwińska and Krzyścin (2024), were used to calculate other biologically weighted daily RE, for previtamin D3 synthesis and clearing of psoriatic lesions.