There is a need for centralized isolation, and there are three types of trip codes: green codes for direct travel, red codes for centralized isolation for 14 days, and yellow codes for isolation for up to seven days. The management information system of each province's "trip code" is based on real data, connected to the dynamic control list of key personnel and other related databases.

The "trip code" is issued according to the results of the verification and comparison of the information declared by the public and the back-end data, and the three-color dynamic management of the public's "green code, red code and yellow code" is implemented.

In order to implement the differentiated prevention and control strategies of each province's zoning, classification and time-sharing, and to promote the resumption of work and the safe and orderly flow of personnel. The provinces in the medium and low risk areas with green code personnel, the province passes; high-risk areas with green code personnel, in accordance with the provisions of the local prevention and control command to travel, the rules of passage within the county by the county (city, district) prevention and control command to determine the rules of passage within the city by the municipal (state) prevention and control command to determine.

Outside the city high-risk areas with a green code and the inflow of people to take "point to point" transportation mode of safe and orderly flow. Holders of yellow code will not be released, holders of red code according to the requirements of epidemic prevention and control by the local admission, isolation.