China’s current standards system is defined by Standardization Law, which came into effect on the 1 January 2018. The standards system consists of five hierarchies of standards: national (i.e. GB/GBT), sector (or ministry) (i.e. JB/T, YY/T, etc.), local (i.e. DB/T), association, and enterprises standards. Among these, national standards are composed of mandatory national standards and recommended (or voluntary) national standards. Apart from Mandatory National Standards, all other standards are voluntary.