[en] Surface area of glass grains by adsorption of methylene blue has been determined. Effects of variables such as pH, glass compositions, and equilibration time on the adsorption of methylene blue on glass surfaces have been evaluated. Conditions to determine relative surface area of glass-pieces/glass-grains by adsorption of methylene blue have been found out. The method has been successfully applied to compare the impact strength of glasses by measuring the surface area of the shattered pieces generated in shattering test unit. (author)