The Nimbus-4 BUV Level-1 Radiance data collection was derived from the Primary Data Base (PDB) product and contains the calibrated and geolocated backscattered ultraviolet radiances measured every 32 seconds at 12 wavelengths between 250 and 340 nm during the daylit orbit portion. The data collection also contains quality flags, dark current analyses of the data, orbital information, and housekeeping data.The data were originally created on IBM 360 machines and archived on magnetic tapes. The data have been restored from the tapes and are now archived on disk in their original IBM binary file format. Each file contains about one orbit of data. The data files consist of 100 4-byte word records which are blocked with up to 25 records. The first record is the header record, followed by a series of data records, and ended with two trailer records. A typical orbit file is about 70 kB in size.The BUV instrument was operational from April 10, 1970 until May 6, 1977. In July 1972 the Nimbus-4 solar power array partially failed such that BUV operations were curtailed. Thus data collected in the later years was increasingly sparse, particularly in the equatorial region.This product was previously available from the NSSDC with the identifier ESAC-00055 (old ID 70-025A-05B).