The UV absorption cross-sections of hydroxyacetone, 3-hydroxy 2-butanone, 4-hydroxy 2-butanone and 3-hydroxy 3-methyl 2-butanone have been measured. The experiments have been carried out between 250 and 363 K using a D2 lamp coupled to a monochromator. This work provides the first UV cross-section measurements for 3-hydroxy 2-butanone, 4-hydroxy 2-butanone and 3-hydroxy 3-methyl 2-butanone. The obtained cross-section values are used to calculate the photolysis rates and to estimate the tropospheric lifetimes of the studied compounds. The results suggest that photolysis could be an important removal process for these species in the troposphere. (C) 2012 Elsevier B. V. All rights reserved.