"HJ 596.5-2010 Water Quality Vocabulary Part 5" is a standard formulated to implement environmental protection laws and regulations, standardize water quality terminology, and protect the environment and human health. This standard is revised from the "Water Quality Vocabulary Parts 1 and 2" and "Water Quality Vocabulary Parts 3 to 7" issued in 1986 and 1989. This part of the vocabulary is designed to describe the characteristics of water quality, including detailed terms and their definitions, and covers the corresponding English terms. During the revision process, reference is made to the international standard "ISO 6107.5-2004 Water Quality Vocabulary Part 5" to maintain the international versatility and accuracy of terms. From March 1, 2011, "GB 6816-86" and "GB 11915-89" will no longer apply. This standard was jointly drafted by the China environment monitoring station and the Liaoning provincial environment monitoring experimental center, and was approved and issued by the Ministry of environment protection on November 5, 2010.