The purpose of this standard is to establish the procedure to determine the liquid limit of a soil through the use of the Casagrande apparatus. The liquid limit is defined, for the purposes of this standard, as the humidity of a soil mixed with water and placed in a standardized spoon, when a furrow, made with a standardized groover, which divides said soil into two halves, is closed. along its bottom over a distance of 13 mm, after having dropped the aforementioned spoon 25 times from a height of 10 mm onto a also standardized base, with a cadence of 2 blows per second.