An ultraviolet (UV) fluorometric sensor measures a chemical concentration in a sample based on the measured fluorescence of the sample. The sensor includes a controller, at least one UV light source, and at least one UV detector. The sensor emits UV light in a wavelength range of 245-265 nm from the light source through the sample in an analytical area. The UV detector measures the fluorescence emission from the sample. The controller transforms output signals from the UV detector into fluorescence values or optical densities for one or more wavelengths in the wavelength range of 265-340 nm. The controller calculates the chemical concentration of the chemical in the sample based on the measured fluorescence emissions.