Four different types of silicate glass specimens were irradiated with gamma radiation using a Co-60 radioisotope. Glass specimens, with four different chemical compositions, were exposed to neutron and mixed neutron/gamma doses in the central thimble and tangential beam tube of the nuclear research reactor. Optical variations were determined in accordance with standardisation concept. Changes in the direct solar absorbance (alpha(e)) of borosilicate glass were examined using the increase in gamma absorbed dose, and results were compared with the changes in the direct solar absorbance of the three different type silicate glass specimens. Solar absorption decreased due to decrease of penetration with absorbed dose. alpha(e) of borosilicate increased considerably when compared with other glass types. Changes in optical density were evaluated as an approach to create dose estimation. Mixed/thermal neutron irradiation on glass caused to increse alpha(e). (C) 2012 Elsevier Masson SAS. All rights reserved.