This standard specifies the mass requirements and safety information for o-nitrochlorobenzene and p-nitrochlorobenzene, including sampling, test methods, inspection rules, marking, labeling, Encasement, transportation and storage. It is applicable to ensure the mass and safety of these two chemicals during production, storage, transportation and use. The molecular formula of o-nitrochlorobenzene and p-nitrochlorobenzene is C H ClNO ³, and the relative molecular mass is 157.55 (according to the 2009 international relative atomic mass). The standard involves multiple normative reference documents, such as the Dangerous Goods Encasement Mark, Chemical Reagent Gas chromatography, CG General Principles and Chemical Safety Technical Specifications, etc., to ensure that the product meets the relevant safety and mass standards.