A person may hold more than one job.
Health certificates are divided into four categories, a is the physical examination of employees in catering industry, food factory, canteen, water plant and water dispenser factory, b is the physical examination of employees in tourism, culture and entertainment, beauty salons, shopping malls, cosmetics factories and health centers, and c is the general occupational recruitment physical examination of general factories and enterprises. Class D is the physical examination of electricians, elevator workers, boiler workers and other high-temperature aerial workers.