Shanghai public place health certificate, post code A, and the post of directly serving customers. What should I check?

The job code is represented by English capital letters A~F respectively: A: the person who directly serves customers in public places; B: personnel engaged in the production and management of drinking water; C: personnel directly engaged in cosmetics production; D: personnel engaged in food circulation and consumption (including health food production and processing, box lunch production); E: employees of food production and processing enterprises; F: Other health certificates (referring to those who are not clearly engaged in the above jobs) are health examination certificates, which prove that you have started health examination. It mainly involves six diseases in five industries, which greatly protects the health of employees and customers.