This standard specifies the basic requirements, technical requirements, test methods, inspection rules, marking, packaging, transportation and storage, safety, and quality commitments of 1,3-difluorobenzene (also known as "m-difluorobenzene"). This standard applies to m-difluorobenzene obtained by diazotization, decomposition and refining using m-phenylenediamine and anhydrous hydrogen fluoride as raw materials. Structural formula: Molecular formula: C6H4F2 Relative molecular mass: 114.09 (according to the relative international atomic mass in 2018)