This standard specifies the requirements, safety information, sampling, test methods, inspection rules, and marking, labeling, packaging, transportation and storage of 3,3'-dichlorobenzidine hydrochloride. This standard applies to the quality control of 3,3'-dichlorobenzidine hydrochloride products. Molecular formula: CHClN ? 2HCl Relative molecular mass: 326.05 (according to the 2009 international relative atomic mass) CAS RN: 612-83-9