On March 16, 2020, at the 36th press conference held by the Zhejiang Provincial Government Information Office, the executive deputy director of the Office of the Leading Group for Prevention and Control of Zhejiang Province and the deputy secretary-general of the provincial government said that Zhejiang regards health codes as a sharp weapon for fine control of classification, and according to the actual situation of returned overseas Chinese, international students and other foreigners, the international version of health codes is launched, and health codes are classified into three categories: orange, yellow and green.