In order to determine K-IC in a simplified form, rectangular pieces of glass were scratched with a glazier’s diamond, considering this scratch as the crack tip. The sides of the crack were made by sticking two rectangular pieces of proper thickness with epoxy resin as was made in a previous work. The K-IC was determined in glass in which the cracks are impregnated with liquid solutions of kerosene, sodium hydroxide and sodium silicate. For the samples impregnated with kerosene the mean value of K-IC remains constant, whereas for the other two solutions a decrease in the mean value of K-IC is observed, a 10% in samples impregnated with sodium hydroxide and 16% in samples impregnated with sodium silicate, when comparing them with their respective groups of samples of glass without impregnating. The corresponding Weibull diagrams were made and Weibull functions of three parameters were obtained. The respective parameters of the probability distribution functions of K-IC were estimated by means of the graphic method of nomograms.