How does Health Code Work
Information Collected
Health Code generally aggregates four types of data to convert exposure risks into color-based codes:
First, each user needs to provide personal information, including name, national ID number, and physical conditions (e.g., fever, tiredness, dry cough). In some cities, people also need to register with facial recognition and update their physical conditions every day.
The second data source is the registered residence information of the public security department.
The third is the travel data, which includes not only the mobile phone signaling location provided by the operator coordinated by the communication management department, but also the travel data of railway and air traffic to judge whether it has reached the risk zone.
Finally, Health Code system also gather the medical information provided by the health and disease control department to evaluate whether there is intersection with the diagnosed person.
Red, Yellow, and Green
People receive a QR-code on smartphones, indicating their exposure risks and mobility. Based on their data, all users are classified into three color-based categories: green, yellow, and red. A green QR code allows an individual to travel within the city; a yellow one implies potential risks that require an at-home quarantine for 7-14 days; and a red code imposes a 14-day quarantine either at home or a centralized location. While the yellow or red code does not necessarily mean the person has the virus, it suggests that the person has a greater risk of infection. Moreover, the status of Health Code is updated at midnight daily. Thus, a user’s green code will be transformed into yellow or red if smartphone GPS data show that the user went to a risky area.
Application scenario
When entering residential quarters, offices, public places and means of transportation, people need to show the health code to the staff before entering, and they can enter only after confirming that the health code is green. Therefore, health code has been used as entry and exit certificate when people entering the above mentioned places during the epidemic.
Other than showing officials the user’s health status, the system also links to a database that officials can monitor carefully. So, say, if an individual’s health status changes and scans the QR code when traveling (on the subway, for instance), the system provides alert and can backtrack where the patient has been and identify people who have been in contact with that individual.
Other Functions
In some areas, the health code can be used for medical institution registration, medical treatment and medical insurance settlement. In order to simplify national travel, the Chinese government has put forward the policies of "one code access" and "multiple codes in one". At present, the health code has been integrated with travel code.
In the future, health code will be integrated with "multi code" applications such as financial payment code and citizen card to become a multi-functional application. It is expected that after the end of the epidemic, the health code will continue to be used as a portable service code for providing data services for citizens (enterprises) in their work, life and operation, and more data and application services will be launched in succession.