HG/T 4739-2014 "Spinning & weaving dyeing and finishing aids, Determination of water content" stipulates a general method for the determination of free water or crystal water content in Spinning & weaving dyeing and finishing aids by Karl Fischer volumetric method. This standard applies to the determination of free water or crystal water in most organic and inorganic solid and liquid products, but does not include strong reducing, ketone-containing, aldehyde-like substances and substances insoluble in methanol. The standard describes in detail the principle of quantitative reaction between the sample and Karl Fischer reagents, and expresses the water content of the sample by mass fraction. In addition, the standard also stipulates that analytically pure reagents and reagents and materials that meet the third-class water standard in GB/T 6682-2008 must be used.